Is there a built-in function to print all the current properties and values of an object

Question

So what I m looking for here is something like PHP s print r function   This is so I can debug my scripts by seeing what s the state of the object in question

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I recommend using help your object    help dir     If called without an argument  return the names in the current scope   Else  return an alphabetized list of names comprising  some of  the attributes  of the given object  and of attributes reachable from it   If the object supplies a method named   dir    it will be used  otherwise  the default dir   logic is used and returns   for a module object  the module s attributes   for a class object   its attributes  and recursively the attributes  of its bases   for any other object  its attributes  its class s attributes  and  recursively the attributes of its class s base classes     help vars    Without arguments  equivalent to locals    With an argument  equivalent to object   dict

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pprint contains a    pretty printer    for producing aesthetically pleasing representations of your data structures  The formatter produces representations of data structures that can be parsed correctly by the interpreter  and are also easy for a human to read  The output is kept on a single line  if possible  and indented when split across multiple lines

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If you re using this for debugging  and you just want a recursive dump of everything  the accepted answer is unsatisfying because it requires that your classes have good   str   implementations already  If that s not the case  this works much better   import json print json dumps YOUR OBJECT                    default lambda obj  vars obj                    indent 1

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A metaprogramming example Dump object with magic      cat dump py      usr bin python import sys if len sys argv   gt  2      module  metaklass    sys argv 1 3      m     import   module  globals    locals     metaklass         metaclass     getattr m  metaklass   class Data      def   init   self           self num   38         self lst     a   b   c           self str    spam      dumps     lambda self  repr self        str     lambda self  self dumps    data   Data   print data   Without arguments      python dump py    lt   main   Data instance at 0x00A052D8 gt    With Gnosis Utils      python dump py gnosis magic MetaXMLPickler        lt  xml version  1 0   gt   lt  DOCTYPE PyObject SYSTEM  PyObjects dtd  gt   lt PyObject module    main    class  Data  id  11038416  gt   lt attr name  lst  type  list  id  11196136   gt     lt item type  string  value  a    gt     lt item type  string  value  b    gt     lt item type  string  value  c    gt   lt  attr gt   lt attr name  num  type  numeric  value  38    gt   lt attr name  str  type  string  value  spam    gt   lt  PyObject gt    It is a bit outdated but still working

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Why not something simple   for key value in obj   dict   iteritems        print key value

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This works no matter how your varibles are defined within a class  inside   init   or outside   your obj   YourObj   attrs with value    attr  getattr your obj  attr  for attr in dir your obj

User · Answer

Just try beeprint   It will help you not only with printing object variables  but beautiful output as well  like this   class NormalClassNewStyle     dicts           lists        static props  1    tupl   1  2

User · Answer

Why not something simple   for key value in obj   dict   iteritems        print key value

User · Answer

Try ppretty  from ppretty import ppretty   class A object       s   5      def   init   self           self  p   8       property     def foo self           return range 10    print ppretty A    show protected True  show static True  show properties True    Output     main   A  p   8  foo    0  1       8  9   s   5

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dir has been mentioned  but that ll only give you the attributes  names   If you want their values as well try   dict     class O     def   init    self         self value   3  o   O     Here is the output    gt  gt  gt  o   dict      value   3

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To print the current state of the object you might     gt  gt  gt  obj   in an interpreter   or   print repr obj    in a script   or  print obj   For your classes define   str   or   repr   methods  From the Python documentation        repr   self  Called by the repr   built-in function and by string   conversions  reverse quotes  to   compute the  official  string   representation of an object  If at all   possible  this should look like a   valid Python expression that could be   used to recreate an object with the   same value  given an appropriate   environment   If this is not possible    a string of the form   lt    some useful   description      should be returned    The return value must be a string   object  If a class defines repr     but not   str      then   repr     is   also used when an  informal  string   representation of instances of that   class is required  This is typically   used for debugging  so it is important   that the representation is   information-rich and unambiguous         str   self  Called by the str   built-in function and by the print   statement to compute the  informal    string representation of an object    This differs from   repr     in that   it does not have to be a valid Python   expression  a more convenient or   concise representation may be used   instead  The return value must be a   string object

User · Answer

A metaprogramming example Dump object with magic      cat dump py      usr bin python import sys if len sys argv   gt  2      module  metaklass    sys argv 1 3      m     import   module  globals    locals     metaklass         metaclass     getattr m  metaklass   class Data      def   init   self           self num   38         self lst     a   b   c           self str    spam      dumps     lambda self  repr self        str     lambda self  self dumps    data   Data   print data   Without arguments      python dump py    lt   main   Data instance at 0x00A052D8 gt    With Gnosis Utils      python dump py gnosis magic MetaXMLPickler        lt  xml version  1 0   gt   lt  DOCTYPE PyObject SYSTEM  PyObjects dtd  gt   lt PyObject module    main    class  Data  id  11038416  gt   lt attr name  lst  type  list  id  11196136   gt     lt item type  string  value  a    gt     lt item type  string  value  b    gt     lt item type  string  value  c    gt   lt  attr gt   lt attr name  num  type  numeric  value  38    gt   lt attr name  str  type  string  value  spam    gt   lt  PyObject gt    It is a bit outdated but still working

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from pprint import pprint  def print r the object       print   CLASS     the object   class     name       BASE CLASS     the object   class     bases            pprint vars the object

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You want vars   mixed with pprint     from pprint import pprint pprint vars your object

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You want vars   mixed with pprint     from pprint import pprint pprint vars your object

User · Answer

You can use the  dir    function to do this    gt  gt  gt  import sys  gt  gt  gt  dir sys      displayhook        doc        excepthook        name        stderr        stdin        stdo t       current frames     getframe    api version    argv    builtin module names    byteorder    call tracing    callstats    copyright    displayhook    dllhandle    exc clear    exc info    exc type    excepthook    exec prefix    executable    exit    getcheckinterval    getdefault ncoding    getfilesystemencoding    getrecursionlimit    getrefcount    getwindowsversion    he version    maxint    maxunicode    meta path    modules    path    path hooks    path importer  ache    platform    prefix    ps1    ps2    setcheckinterval    setprofile    setrecursionlimit    settrace    stderr    stdin    stdout    subversion    version    version info    warnoption     winver    gt  gt  gt    Another useful feature is help    gt  gt  gt  help sys  Help on built-in module sys   NAME     sys  FILE      built-in   MODULE DOCS     http   www python org doc current lib module-sys html  DESCRIPTION     This module provides access to some objects used or maintained by the     interpreter and to functions that interact strongly with the interpreter       Dynamic objects       argv -- command line arguments  argv 0  is the script pathname if known

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You can try the Flask Debug Toolbar  https   pypi python org pypi Flask-DebugToolbar  from flask import Flask from flask debugtoolbar import DebugToolbarExtension  app   Flask   name       the toolbar is only enabled in debug mode  app debug   True    set a  SECRET KEY  to enable the Flask session cookies app config  SECRET KEY       lt replace with a secret key gt    toolbar   DebugToolbarExtension app

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Try ppretty  from ppretty import ppretty   class A object       s   5      def   init   self           self  p   8       property     def foo self           return range 10    print ppretty A    show protected True  show static True  show properties True    Output     main   A  p   8  foo    0  1       8  9   s   5

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If you re using this for debugging  and you just want a recursive dump of everything  the accepted answer is unsatisfying because it requires that your classes have good   str   implementations already  If that s not the case  this works much better   import json print json dumps YOUR OBJECT                    default lambda obj  vars obj                    indent 1

User · Answer

def dump obj     for attr in dir obj       print  obj  s    r     attr  getattr obj  attr      There are many 3rd-party functions out there that add things like exception handling  national special character printing  recursing into nested objects etc  according to their authors  preferences  But they all basically boil down to this

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def dump obj     for attr in dir obj       print  obj  s    r     attr  getattr obj  attr      There are many 3rd-party functions out there that add things like exception handling  national special character printing  recursing into nested objects etc  according to their authors  preferences  But they all basically boil down to this

User · Answer

dir has been mentioned  but that ll only give you the attributes  names   If you want their values as well try   dict     class O     def   init    self         self value   3  o   O     Here is the output    gt  gt  gt  o   dict      value   3

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To dump  myObject    from bson import json util import json  print json dumps myObject  default json util default  sort keys True  indent 4  separators                 I tried vars   and dir    both failed for what I was looking for  vars   didn t work because the object didn t have   dict    exceptions TypeError  vars   argument must have   dict   attribute   dir   wasn t what I was looking for  it s just a listing of field names  doesn t give the values or the object structure   I think json dumps   would work for most objects without the default json util default  but I had a datetime field in the object so the standard json serializer failed  See How to overcome  quot datetime datetime not JSON serializable quot  in python

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In most cases  using   dict   or dir   will get you the info you re wanting  If you should happen to need more details  the standard library includes the inspect module  which allows you to get some impressive amount of detail  Some of the real nuggests of info include    names of function and method parameters class hierarchies source code of the implementation of a functions class objects local variables out of a frame object   If you re just looking for  what attribute values does my object have    then dir   and   dict   are probably sufficient  If you re really looking to dig into the current state of arbitrary objects  keeping in mind that in python almost everything is an object   then inspect is worthy of consideration

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You are really mixing together two different things   Use dir    vars   or the inspect module to get what you are interested in  I use   builtins   as an example  you can use any object instead     gt  gt  gt  l   dir   builtins     gt  gt  gt  d     builtins     dict     Print that dictionary however fancy you like    gt  gt  gt  print l   ArithmeticError    AssertionError    AttributeError        or   gt  gt  gt  from pprint import pprint  gt  gt  gt  pprint l    ArithmeticError     AssertionError     AttributeError     BaseException     DeprecationWarning         gt  gt  gt  pprint d  indent 2     ArithmeticError    lt type  exceptions ArithmeticError  gt      AssertionError    lt type  exceptions AssertionError  gt      AttributeError    lt type  exceptions AttributeError  gt                 ArithmeticError             AssertionError             AttributeError             BaseException             DeprecationWarning         Pretty printing is also available in the interactive debugger as a command    Pdb  pp vars       builtins       ArithmeticError    lt type  exceptions ArithmeticError  gt                      AssertionError    lt type  exceptions AssertionError  gt                      AttributeError    lt type  exceptions AttributeError  gt                      BaseException    lt type  exceptions BaseException  gt                      BufferError    lt type  exceptions BufferError  gt                                            zip    lt built-in function zip gt        file      pass py       name        main

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You can try the Flask Debug Toolbar  https   pypi python org pypi Flask-DebugToolbar  from flask import Flask from flask debugtoolbar import DebugToolbarExtension  app   Flask   name       the toolbar is only enabled in debug mode  app debug   True    set a  SECRET KEY  to enable the Flask session cookies app config  SECRET KEY       lt replace with a secret key gt    toolbar   DebugToolbarExtension app

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To print the current state of the object you might     gt  gt  gt  obj   in an interpreter   or   print repr obj    in a script   or  print obj   For your classes define   str   or   repr   methods  From the Python documentation        repr   self  Called by the repr   built-in function and by string   conversions  reverse quotes  to   compute the  official  string   representation of an object  If at all   possible  this should look like a   valid Python expression that could be   used to recreate an object with the   same value  given an appropriate   environment   If this is not possible    a string of the form   lt    some useful   description      should be returned    The return value must be a string   object  If a class defines repr     but not   str      then   repr     is   also used when an  informal  string   representation of instances of that   class is required  This is typically   used for debugging  so it is important   that the representation is   information-rich and unambiguous         str   self  Called by the str   built-in function and by the print   statement to compute the  informal    string representation of an object    This differs from   repr     in that   it does not have to be a valid Python   expression  a more convenient or   concise representation may be used   instead  The return value must be a   string object

User · Answer

You want vars   mixed with pprint     from pprint import pprint pprint vars your object

User · Answer

from pprint import pprint  def print r the object       print   CLASS     the object   class     name       BASE CLASS     the object   class     bases            pprint vars the object

User · Answer

dir has been mentioned  but that ll only give you the attributes  names   If you want their values as well try   dict     class O     def   init    self         self value   3  o   O     Here is the output    gt  gt  gt  o   dict      value   3

User · Answer

This works no matter how your varibles are defined within a class  inside   init   or outside   your obj   YourObj   attrs with value    attr  getattr your obj  attr  for attr in dir your obj

User · Answer

A metaprogramming example Dump object with magic      cat dump py      usr bin python import sys if len sys argv   gt  2      module  metaklass    sys argv 1 3      m     import   module  globals    locals     metaklass         metaclass     getattr m  metaklass   class Data      def   init   self           self num   38         self lst     a   b   c           self str    spam      dumps     lambda self  repr self        str     lambda self  self dumps    data   Data   print data   Without arguments      python dump py    lt   main   Data instance at 0x00A052D8 gt    With Gnosis Utils      python dump py gnosis magic MetaXMLPickler        lt  xml version  1 0   gt   lt  DOCTYPE PyObject SYSTEM  PyObjects dtd  gt   lt PyObject module    main    class  Data  id  11038416  gt   lt attr name  lst  type  list  id  11196136   gt     lt item type  string  value  a    gt     lt item type  string  value  b    gt     lt item type  string  value  c    gt   lt  attr gt   lt attr name  num  type  numeric  value  38    gt   lt attr name  str  type  string  value  spam    gt   lt  PyObject gt    It is a bit outdated but still working

User · Answer

pprint contains a    pretty printer    for producing aesthetically pleasing representations of your data structures  The formatter produces representations of data structures that can be parsed correctly by the interpreter  and are also easy for a human to read  The output is kept on a single line  if possible  and indented when split across multiple lines

User · Answer

Just try beeprint   It will help you not only with printing object variables  but beautiful output as well  like this   class NormalClassNewStyle     dicts           lists        static props  1    tupl   1  2

User · Answer

Is there a built-in function to print all the current properties and values of an object    No  The most upvoted answer excludes some kinds of attributes  and the accepted answer shows how to get all attributes  including methods and parts of the non-public api  But there is no good complete builtin function for this   So the short corollary is that you can write your own  but it will calculate properties and other calculated data-descriptors that are part of the public API  and you might not want that   from pprint import pprint from inspect import getmembers from types import FunctionType  def attributes obj       disallowed names           name for name  value in getmembers type obj            if isinstance value  FunctionType       return         name  getattr obj  name  for name in dir obj           if name 0         and name not in disallowed names and hasattr obj  name    def print attributes obj       pprint attributes obj     Problems with other answers  Observe the application of the currently top voted answer on a class with a lot of different kinds of data members   from pprint import pprint  class Obj        slots      foo    bar      dict        def   init   self  baz           self foo              self bar   0         self baz   baz      property     def quux self           return self foo   self bar  obj   Obj  baz   pprint vars obj     only prints     baz    baz     Because vars only returns the   dict   of an object  and it s not a copy  so if you modify the dict returned by vars  you re also modifying the   dict   of the object itself   vars obj   quux      WHAT    vars obj    returns     baz    baz    quux    WHAT       -- which is bad because quux is a property that we shouldn t be setting and shouldn t be in the namespace     Applying the advice in the currently accepted answer  and others  is not much better    gt  gt  gt  dir obj      class        delattr        dict        dir        doc        eq        format        ge        getattribute        gt        hash        init        init subclass        le        lt        module        ne        new        reduce        reduce ex        repr        setattr        sizeof        slots        str        subclasshook      bar    baz    foo    quux     As we can see  dir only returns all  actually just most  of the names associated with an object   inspect getmembers  mentioned in the comments  is similarly flawed - it returns all names and values   From class  When teaching I have my students create a function that provides the semantically public API of an object   def api obj       return  name for name in dir obj  if name 0            We can extend this to provide a copy of the semantic namespace of an object  but we need to exclude   slots   that aren t assigned  and if we re taking the request for  current properties  seriously  we need to exclude calculated properties  as they could become expensive  and could be interpreted as not  current     from types import FunctionType from inspect import getmembers  def attrs obj        disallowed properties            name for name  value in getmembers type obj             if isinstance value   property  FunctionType         return          name  getattr obj  name  for name in api obj            if name not in disallowed properties and hasattr obj  name     And now we do not calculate or show the property  quux    gt  gt  gt  attrs obj    bar   0   baz    baz    foo         Caveats  But perhaps we do know our properties aren t expensive  We may want to alter the logic to include them as well  And perhaps we want to exclude other custom data descriptors instead   Then we need to further customize this function  And so it makes sense that we cannot have a built-in function that magically knows exactly what we want and provides it  This is functionality we need to create ourselves   Conclusion  There is no built-in function that does this  and you should do what is most semantically appropriate for your situation

User · Answer

I like working with python object built-in types keys or values     For attributes regardless they are methods or variables    o keys     For values of those attributes   o values

User · Answer

To print the current state of the object you might     gt  gt  gt  obj   in an interpreter   or   print repr obj    in a script   or  print obj   For your classes define   str   or   repr   methods  From the Python documentation        repr   self  Called by the repr   built-in function and by string   conversions  reverse quotes  to   compute the  official  string   representation of an object  If at all   possible  this should look like a   valid Python expression that could be   used to recreate an object with the   same value  given an appropriate   environment   If this is not possible    a string of the form   lt    some useful   description      should be returned    The return value must be a string   object  If a class defines repr     but not   str      then   repr     is   also used when an  informal  string   representation of instances of that   class is required  This is typically   used for debugging  so it is important   that the representation is   information-rich and unambiguous         str   self  Called by the str   built-in function and by the print   statement to compute the  informal    string representation of an object    This differs from   repr     in that   it does not have to be a valid Python   expression  a more convenient or   concise representation may be used   instead  The return value must be a   string object

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I was needing to print DEBUG info in some logs and was unable to use pprint because it would break it   Instead I did this and got virtually the same thing   DO   DemoObject    itemDir   DO   dict    for i in itemDir      print   0       1   format i  itemDir i

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This prints out all the object contents recursively in json or yaml indented format   import jsonpickle   pip install jsonpickle import json import yaml   pip install pyyaml  serialized   jsonpickle encode obj  max depth 2    max depth is optional print json dumps json loads serialized   indent 4  print yaml dump yaml load serialized   indent 4

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This prints out all the object contents recursively in json or yaml indented format   import jsonpickle   pip install jsonpickle import json import yaml   pip install pyyaml  serialized   jsonpickle encode obj  max depth 2    max depth is optional print json dumps json loads serialized   indent 4  print yaml dump yaml load serialized   indent 4

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dir has been mentioned  but that ll only give you the attributes  names   If you want their values as well try   dict     class O     def   init    self         self value   3  o   O     Here is the output    gt  gt  gt  o   dict      value   3

User · Answer

Is there a built-in function to print all the current properties and values of an object    No  The most upvoted answer excludes some kinds of attributes  and the accepted answer shows how to get all attributes  including methods and parts of the non-public api  But there is no good complete builtin function for this   So the short corollary is that you can write your own  but it will calculate properties and other calculated data-descriptors that are part of the public API  and you might not want that   from pprint import pprint from inspect import getmembers from types import FunctionType  def attributes obj       disallowed names           name for name  value in getmembers type obj            if isinstance value  FunctionType       return         name  getattr obj  name  for name in dir obj           if name 0         and name not in disallowed names and hasattr obj  name    def print attributes obj       pprint attributes obj     Problems with other answers  Observe the application of the currently top voted answer on a class with a lot of different kinds of data members   from pprint import pprint  class Obj        slots      foo    bar      dict        def   init   self  baz           self foo              self bar   0         self baz   baz      property     def quux self           return self foo   self bar  obj   Obj  baz   pprint vars obj     only prints     baz    baz     Because vars only returns the   dict   of an object  and it s not a copy  so if you modify the dict returned by vars  you re also modifying the   dict   of the object itself   vars obj   quux      WHAT    vars obj    returns     baz    baz    quux    WHAT       -- which is bad because quux is a property that we shouldn t be setting and shouldn t be in the namespace     Applying the advice in the currently accepted answer  and others  is not much better    gt  gt  gt  dir obj      class        delattr        dict        dir        doc        eq        format        ge        getattribute        gt        hash        init        init subclass        le        lt        module        ne        new        reduce        reduce ex        repr        setattr        sizeof        slots        str        subclasshook      bar    baz    foo    quux     As we can see  dir only returns all  actually just most  of the names associated with an object   inspect getmembers  mentioned in the comments  is similarly flawed - it returns all names and values   From class  When teaching I have my students create a function that provides the semantically public API of an object   def api obj       return  name for name in dir obj  if name 0            We can extend this to provide a copy of the semantic namespace of an object  but we need to exclude   slots   that aren t assigned  and if we re taking the request for  current properties  seriously  we need to exclude calculated properties  as they could become expensive  and could be interpreted as not  current     from types import FunctionType from inspect import getmembers  def attrs obj        disallowed properties            name for name  value in getmembers type obj             if isinstance value   property  FunctionType         return          name  getattr obj  name  for name in api obj            if name not in disallowed properties and hasattr obj  name     And now we do not calculate or show the property  quux    gt  gt  gt  attrs obj    bar   0   baz    baz    foo         Caveats  But perhaps we do know our properties aren t expensive  We may want to alter the logic to include them as well  And perhaps we want to exclude other custom data descriptors instead   Then we need to further customize this function  And so it makes sense that we cannot have a built-in function that magically knows exactly what we want and provides it  This is functionality we need to create ourselves   Conclusion  There is no built-in function that does this  and you should do what is most semantically appropriate for your situation

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I ve upvoted the answer that mentions only pprint  To be clear  if you  want to see all the values in a complex data structure  then do something like   from pprint import pprint pprint my var    Where my var is your variable of interest  When I used pprint vars my var   I got nothing  and other answers here didn t help or the method looked unnecessarily long  By the way  in my particular case  the code I was inspecting had a dictionary of dictionaries   Worth pointing out that with some custom classes you may just end up with an unhelpful  lt someobject ExampleClass object at 0x7f739267f400 gt  kind of output  In that case  you might have to implement a   str   method  or try some of the other solutions  I d still like to find something simple that works in all scenarios  without third party libraries

User · Answer

You want vars   mixed with pprint     from pprint import pprint pprint vars your object

User · Answer

def dump obj     for attr in dir obj       print  obj  s    r     attr  getattr obj  attr      There are many 3rd-party functions out there that add things like exception handling  national special character printing  recursing into nested objects etc  according to their authors  preferences  But they all basically boil down to this

User · Answer

To dump  myObject    from bson import json util import json  print json dumps myObject  default json util default  sort keys True  indent 4  separators                 I tried vars   and dir    both failed for what I was looking for  vars   didn t work because the object didn t have   dict    exceptions TypeError  vars   argument must have   dict   attribute   dir   wasn t what I was looking for  it s just a listing of field names  doesn t give the values or the object structure   I think json dumps   would work for most objects without the default json util default  but I had a datetime field in the object so the standard json serializer failed  See How to overcome  quot datetime datetime not JSON serializable quot  in python

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You are really mixing together two different things   Use dir    vars   or the inspect module to get what you are interested in  I use   builtins   as an example  you can use any object instead     gt  gt  gt  l   dir   builtins     gt  gt  gt  d     builtins     dict     Print that dictionary however fancy you like    gt  gt  gt  print l   ArithmeticError    AssertionError    AttributeError        or   gt  gt  gt  from pprint import pprint  gt  gt  gt  pprint l    ArithmeticError     AssertionError     AttributeError     BaseException     DeprecationWarning         gt  gt  gt  pprint d  indent 2     ArithmeticError    lt type  exceptions ArithmeticError  gt      AssertionError    lt type  exceptions AssertionError  gt      AttributeError    lt type  exceptions AttributeError  gt                 ArithmeticError             AssertionError             AttributeError             BaseException             DeprecationWarning         Pretty printing is also available in the interactive debugger as a command    Pdb  pp vars       builtins       ArithmeticError    lt type  exceptions ArithmeticError  gt                      AssertionError    lt type  exceptions AssertionError  gt                      AttributeError    lt type  exceptions AttributeError  gt                      BaseException    lt type  exceptions BaseException  gt                      BufferError    lt type  exceptions BufferError  gt                                            zip    lt built-in function zip gt        file      pass py       name        main

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For everybody struggling with    vars   not returning all attributes   dir   not returning the attributes  values    The following code prints all attributes of obj with their values   for attr in dir obj           try              print  obj          format attr  getattr obj  attr            except AttributeError              print  obj         format attr

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I like working with python object built-in types keys or values     For attributes regardless they are methods or variables    o keys     For values of those attributes   o values

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Might be worth checking out --  Is there a Python equivalent to Perl  39 s Data  Dumper   My recommendation is this --  https   gist github com 1071857  Note that perl has a module called Data  Dumper which translates object data back to perl source code  NB  it does NOT translate code back to source  and almost always you don t want to the object method functions in the output   This can be used for persistence  but the common purpose is for debugging   There are a number of things standard python pprint fails to achieve  in particular it just stops descending when it sees an instance of an object and gives you the internal hex pointer of the object  errr  that pointer is not a whole lot of use by the way   So in a nutshell  python is all about this great object oriented paradigm  but the tools you get out of the box are designed for working with something other than objects   The perl Data  Dumper allows you to control how deep you want to go  and also detects circular linked structures  that s really important   This process is fundamentally easier to achieve in perl because objects have no particular magic beyond their blessing  a universally well defined process

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I ve upvoted the answer that mentions only pprint  To be clear  if you  want to see all the values in a complex data structure  then do something like   from pprint import pprint pprint my var    Where my var is your variable of interest  When I used pprint vars my var   I got nothing  and other answers here didn t help or the method looked unnecessarily long  By the way  in my particular case  the code I was inspecting had a dictionary of dictionaries   Worth pointing out that with some custom classes you may just end up with an unhelpful  lt someobject ExampleClass object at 0x7f739267f400 gt  kind of output  In that case  you might have to implement a   str   method  or try some of the other solutions  I d still like to find something simple that works in all scenarios  without third party libraries

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Might be worth checking out --  Is there a Python equivalent to Perl  39 s Data  Dumper   My recommendation is this --  https   gist github com 1071857  Note that perl has a module called Data  Dumper which translates object data back to perl source code  NB  it does NOT translate code back to source  and almost always you don t want to the object method functions in the output   This can be used for persistence  but the common purpose is for debugging   There are a number of things standard python pprint fails to achieve  in particular it just stops descending when it sees an instance of an object and gives you the internal hex pointer of the object  errr  that pointer is not a whole lot of use by the way   So in a nutshell  python is all about this great object oriented paradigm  but the tools you get out of the box are designed for working with something other than objects   The perl Data  Dumper allows you to control how deep you want to go  and also detects circular linked structures  that s really important   This process is fundamentally easier to achieve in perl because objects have no particular magic beyond their blessing  a universally well defined process

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A metaprogramming example Dump object with magic      cat dump py      usr bin python import sys if len sys argv   gt  2      module  metaklass    sys argv 1 3      m     import   module  globals    locals     metaklass         metaclass     getattr m  metaklass   class Data      def   init   self           self num   38         self lst     a   b   c           self str    spam      dumps     lambda self  repr self        str     lambda self  self dumps    data   Data   print data   Without arguments      python dump py    lt   main   Data instance at 0x00A052D8 gt    With Gnosis Utils      python dump py gnosis magic MetaXMLPickler        lt  xml version  1 0   gt   lt  DOCTYPE PyObject SYSTEM  PyObjects dtd  gt   lt PyObject module    main    class  Data  id  11038416  gt   lt attr name  lst  type  list  id  11196136   gt     lt item type  string  value  a    gt     lt item type  string  value  b    gt     lt item type  string  value  c    gt   lt  attr gt   lt attr name  num  type  numeric  value  38    gt   lt attr name  str  type  string  value  spam    gt   lt  PyObject gt    It is a bit outdated but still working

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In most cases  using   dict   or dir   will get you the info you re wanting  If you should happen to need more details  the standard library includes the inspect module  which allows you to get some impressive amount of detail  Some of the real nuggests of info include    names of function and method parameters class hierarchies source code of the implementation of a functions class objects local variables out of a frame object   If you re just looking for  what attribute values does my object have    then dir   and   dict   are probably sufficient  If you re really looking to dig into the current state of arbitrary objects  keeping in mind that in python almost everything is an object   then inspect is worthy of consideration

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I recommend using help your object    help dir     If called without an argument  return the names in the current scope   Else  return an alphabetized list of names comprising  some of  the attributes  of the given object  and of attributes reachable from it   If the object supplies a method named   dir    it will be used  otherwise  the default dir   logic is used and returns   for a module object  the module s attributes   for a class object   its attributes  and recursively the attributes  of its bases   for any other object  its attributes  its class s attributes  and  recursively the attributes of its class s base classes     help vars    Without arguments  equivalent to locals    With an argument  equivalent to object   dict

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def dump obj     for attr in dir obj       print  obj  s    r     attr  getattr obj  attr      There are many 3rd-party functions out there that add things like exception handling  national special character printing  recursing into nested objects etc  according to their authors  preferences  But they all basically boil down to this

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You are really mixing together two different things   Use dir    vars   or the inspect module to get what you are interested in  I use   builtins   as an example  you can use any object instead     gt  gt  gt  l   dir   builtins     gt  gt  gt  d     builtins     dict     Print that dictionary however fancy you like    gt  gt  gt  print l   ArithmeticError    AssertionError    AttributeError        or   gt  gt  gt  from pprint import pprint  gt  gt  gt  pprint l    ArithmeticError     AssertionError     AttributeError     BaseException     DeprecationWarning         gt  gt  gt  pprint d  indent 2     ArithmeticError    lt type  exceptions ArithmeticError  gt      AssertionError    lt type  exceptions AssertionError  gt      AttributeError    lt type  exceptions AttributeError  gt                 ArithmeticError             AssertionError             AttributeError             BaseException             DeprecationWarning         Pretty printing is also available in the interactive debugger as a command    Pdb  pp vars       builtins       ArithmeticError    lt type  exceptions ArithmeticError  gt                      AssertionError    lt type  exceptions AssertionError  gt                      AttributeError    lt type  exceptions AttributeError  gt                      BaseException    lt type  exceptions BaseException  gt                      BufferError    lt type  exceptions BufferError  gt                                            zip    lt built-in function zip gt        file      pass py       name        main

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For everybody struggling with    vars   not returning all attributes   dir   not returning the attributes  values    The following code prints all attributes of obj with their values   for attr in dir obj           try              print  obj          format attr  getattr obj  attr            except AttributeError              print  obj         format attr

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You are really mixing together two different things   Use dir    vars   or the inspect module to get what you are interested in  I use   builtins   as an example  you can use any object instead     gt  gt  gt  l   dir   builtins     gt  gt  gt  d     builtins     dict     Print that dictionary however fancy you like    gt  gt  gt  print l   ArithmeticError    AssertionError    AttributeError        or   gt  gt  gt  from pprint import pprint  gt  gt  gt  pprint l    ArithmeticError     AssertionError     AttributeError     BaseException     DeprecationWarning         gt  gt  gt  pprint d  indent 2     ArithmeticError    lt type  exceptions ArithmeticError  gt      AssertionError    lt type  exceptions AssertionError  gt      AttributeError    lt type  exceptions AttributeError  gt                 ArithmeticError             AssertionError             AttributeError             BaseException             DeprecationWarning         Pretty printing is also available in the interactive debugger as a command    Pdb  pp vars       builtins       ArithmeticError    lt type  exceptions ArithmeticError  gt                      AssertionError    lt type  exceptions AssertionError  gt                      AttributeError    lt type  exceptions AttributeError  gt                      BaseException    lt type  exceptions BaseException  gt                      BufferError    lt type  exceptions BufferError  gt                                            zip    lt built-in function zip gt        file      pass py       name        main

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I was needing to print DEBUG info in some logs and was unable to use pprint because it would break it   Instead I did this and got virtually the same thing   DO   DemoObject    itemDir   DO   dict    for i in itemDir      print   0       1   format i  itemDir i

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You can use the  dir    function to do this    gt  gt  gt  import sys  gt  gt  gt  dir sys      displayhook        doc        excepthook        name        stderr        stdin        stdo t       current frames     getframe    api version    argv    builtin module names    byteorder    call tracing    callstats    copyright    displayhook    dllhandle    exc clear    exc info    exc type    excepthook    exec prefix    executable    exit    getcheckinterval    getdefault ncoding    getfilesystemencoding    getrecursionlimit    getrefcount    getwindowsversion    he version    maxint    maxunicode    meta path    modules    path    path hooks    path importer  ache    platform    prefix    ps1    ps2    setcheckinterval    setprofile    setrecursionlimit    settrace    stderr    stdin    stdout    subversion    version    version info    warnoption     winver    gt  gt  gt    Another useful feature is help    gt  gt  gt  help sys  Help on built-in module sys   NAME     sys  FILE      built-in   MODULE DOCS     http   www python org doc current lib module-sys html  DESCRIPTION     This module provides access to some objects used or maintained by the     interpreter and to functions that interact strongly with the interpreter       Dynamic objects       argv -- command line arguments  argv 0  is the script pathname if known

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In most cases  using   dict   or dir   will get you the info you re wanting  If you should happen to need more details  the standard library includes the inspect module  which allows you to get some impressive amount of detail  Some of the real nuggests of info include    names of function and method parameters class hierarchies source code of the implementation of a functions class objects local variables out of a frame object   If you re just looking for  what attribute values does my object have    then dir   and   dict   are probably sufficient  If you re really looking to dig into the current state of arbitrary objects  keeping in mind that in python almost everything is an object   then inspect is worthy of consideration

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You can use the  dir    function to do this    gt  gt  gt  import sys  gt  gt  gt  dir sys      displayhook        doc        excepthook        name        stderr        stdin        stdo t       current frames     getframe    api version    argv    builtin module names    byteorder    call tracing    callstats    copyright    displayhook    dllhandle    exc clear    exc info    exc type    excepthook    exec prefix    executable    exit    getcheckinterval    getdefault ncoding    getfilesystemencoding    getrecursionlimit    getrefcount    getwindowsversion    he version    maxint    maxunicode    meta path    modules    path    path hooks    path importer  ache    platform    prefix    ps1    ps2    setcheckinterval    setprofile    setrecursionlimit    settrace    stderr    stdin    stdout    subversion    version    version info    warnoption     winver    gt  gt  gt    Another useful feature is help    gt  gt  gt  help sys  Help on built-in module sys   NAME     sys  FILE      built-in   MODULE DOCS     http   www python org doc current lib module-sys html  DESCRIPTION     This module provides access to some objects used or maintained by the     interpreter and to functions that interact strongly with the interpreter       Dynamic objects       argv -- command line arguments  argv 0  is the script pathname if known

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You can use the  dir    function to do this    gt  gt  gt  import sys  gt  gt  gt  dir sys      displayhook        doc        excepthook        name        stderr        stdin        stdo t       current frames     getframe    api version    argv    builtin module names    byteorder    call tracing    callstats    copyright    displayhook    dllhandle    exc clear    exc info    exc type    excepthook    exec prefix    executable    exit    getcheckinterval    getdefault ncoding    getfilesystemencoding    getrecursionlimit    getrefcount    getwindowsversion    he version    maxint    maxunicode    meta path    modules    path    path hooks    path importer  ache    platform    prefix    ps1    ps2    setcheckinterval    setprofile    setrecursionlimit    settrace    stderr    stdin    stdout    subversion    version    version info    warnoption     winver    gt  gt  gt    Another useful feature is help    gt  gt  gt  help sys  Help on built-in module sys   NAME     sys  FILE      built-in   MODULE DOCS     http   www python org doc current lib module-sys html  DESCRIPTION     This module provides access to some objects used or maintained by the     interpreter and to functions that interact strongly with the interpreter       Dynamic objects       argv -- command line arguments  argv 0  is the script pathname if known

User · Answer

In most cases  using   dict   or dir   will get you the info you re wanting  If you should happen to need more details  the standard library includes the inspect module  which allows you to get some impressive amount of detail  Some of the real nuggests of info include    names of function and method parameters class hierarchies source code of the implementation of a functions class objects local variables out of a frame object   If you re just looking for  what attribute values does my object have    then dir   and   dict   are probably sufficient  If you re really looking to dig into the current state of arbitrary objects  keeping in mind that in python almost everything is an object   then inspect is worthy of consideration

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To print the current state of the object you might     gt  gt  gt  obj   in an interpreter   or   print repr obj    in a script   or  print obj   For your classes define   str   or   repr   methods  From the Python documentation        repr   self  Called by the repr   built-in function and by string   conversions  reverse quotes  to   compute the  official  string   representation of an object  If at all   possible  this should look like a   valid Python expression that could be   used to recreate an object with the   same value  given an appropriate   environment   If this is not possible    a string of the form   lt    some useful   description      should be returned    The return value must be a string   object  If a class defines repr     but not   str      then   repr     is   also used when an  informal  string   representation of instances of that   class is required  This is typically   used for debugging  so it is important   that the representation is   information-rich and unambiguous         str   self  Called by the str   built-in function and by the print   statement to compute the  informal    string representation of an object    This differs from   repr     in that   it does not have to be a valid Python   expression  a more convenient or   concise representation may be used   instead  The return value must be a   string object

[python] Is there a built-in function to print all the current properties and values of an object?

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