How can I create an object and add attributes to it

Question

I want to create a dynamic object  inside another object  in Python and then add attributes to it   I tried   obj   someobject obj a   object   setattr obj a   somefield    somevalue     but this didn t work   Any ideas   edit   I am setting the attributes from a for loop which loops through a list of values  e g   params     attr1    attr2    attr3   obj   someobject obj a   object    for p in params     obj a p   where p comes from for loop variable   In the above example I would get obj a attr1  obj a attr2  obj a attr3     I used the setattr function because I didn t know how to do obj a NAME from a for loop   How would I set the attribute based on the value of p in the example above

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Other way i see  this way   import maya cmds  def getData objets None  attrs None       di          for obj in objets          name   str obj          di name             for at in attrs              di name  append cmds getAttr name     at  0       return di  acns cmds ls  L vest     type  aimConstraint   attrs   offset   aimVector   upVector   worldUpVector    getData acns attrs

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I think the easiest way is through the collections module  import collections FinanceCtaCteM   collections namedtuple  FinanceCtaCte    forma pago doc pago get total   def get total    return 98989898 financtacteobj   FinanceCtaCteM forma pago  CONTADO   doc pago  EFECTIVO                                   get total get total   print financtacteobj get total   print financtacteobj forma pago print financtacteobj doc pago

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These solutions are very helpful during testing  Building on everyone else s answers I do this in Python 2 7 9  without staticmethod I get a TypeError  unbound method       In  11   auth   type             In  12   auth func   staticmethod lambda i  i   2  In  13   auth func 2  Out 13   4

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Try the code below     python  gt  gt  gt  class Container object           pass       gt  gt  gt  x   Container    gt  gt  gt  x a   10  gt  gt  gt  x b   20  gt  gt  gt  x banana   100  gt  gt  gt  x a  x b  x banana  10  20  100   gt  gt  gt  dir x      class        delattr        dict        doc        format         getattribute        hash        init        module        new        reduce        reduce ex        repr        setattr            sizeof         str        subclasshook        weakref      a    b    banana

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If we can determine and aggregate all the attributes and values together before creating the nested object  then we could create a new class that takes a dictionary argument on creation     python 2 7  class NestedObject        def   init   self  initial attrs           for key in initial attrs              setattr self  key  initial attrs key    obj   someobject attributes      attr1    val1    attr2    val2    attr3    val3    obj a   NestedObject attributes   gt  gt  gt  obj a attr1  val1   gt  gt  gt  obj a attr2  val2   gt  gt  gt  obj a attr3  val3    We can also allow keyword arguments  See this post    class NestedObject object       def   init   self   initial attrs    kwargs           for dictionary in initial attrs              for key in dictionary                  setattr self  key  dictionary key           for key in kwargs              setattr self  key  kwargs key     obj a   NestedObject attr1  val1   attr2  val2   attr3   val3

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There is types SimpleNamespace class in Python 3 3    obj   someobject obj a   SimpleNamespace   for p in params      setattr obj a  p  value    obj a attr1   collections namedtuple  typing NamedTuple could be used for immutable objects  PEP 557 -- Data Classes  suggests a mutable alternative   For a richer functionality  you could try attrs package  See an example usage

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You could use my ancient Bunch recipe  but if you don t want to make a  bunch class   a very simple one already exists in Python -- all functions can have arbitrary attributes  including lambda functions    So  the following works   obj   someobject obj a   lambda  None setattr obj a   somefield    somevalue     Whether the loss of clarity compared to the venerable Bunch recipe is OK  is a style decision I will of course leave up to you

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di      for x in range 20       name     id s    x     di name    type name   object           setattr di name    attr    value

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Now you can do  not sure if it s the same answer as evilpie    MyObject   type  MyObject    object        obj   MyObject   obj value   42

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Coming to this late in the day but here is my pennyworth with an object that just happens to hold some useful paths in an app but you can adapt it for anything where you want a sorta dict of information that you can access with getattr and dot notation  which is what I think this question is really about    import os  def x path path name       return getattr x path  path name   x path root     home x  for name in   repository    caches    projects        setattr x path  name  os path join x path root  name     This is cool because now   In  1   x path projects Out 1     home x projects   In  2   x path  caches   Out 2     home x caches    So this uses the function object like the above answers but uses the function to get the values  you can still use  getattr  x path   repository   rather than x path  repository   if you prefer

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as docs say      Note  object does not have a   dict    so you can   t assign arbitrary attributes to an instance of the object class    You could just use dummy-class instance

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Which objects are you using  Just tried that with a sample class and it worked fine   class MyClass    i   123456   def f self       return  hello world   b   MyClass   b c   MyClass   setattr b c   test   123  b c test   And I got 123 as the answer   The only situation where I see this failing is if you re trying a setattr on a builtin object   Update  From the comment this is a repetition of  Why can  39 t you add attributes to object in python

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There are a few ways to reach this goal  Basically you need an object which is extendable   obj a   type  Test    object          obj a b    fun     obj b   lambda None  class Test    pass obj c   Test

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You can also use a class object directly  it creates a namespace   class a  pass a somefield1    somevalue1  setattr a   somefield2    somevalue2

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The built-in object can be instantiated but can t have any attributes set on it    I wish it could  for this exact purpose    It doesn t have a   dict   to hold the attributes   I generally just do this   class Object object       pass  a   Object   a somefield   somevalue   When I can  I give the Object class a more meaningful name  depending on what kind of data I m putting in it   Some people do a different thing  where they use a sub-class of dict that allows attribute access to get at the keys   d key instead of d  key     Edit  For the addition to your question  using setattr is fine   You just can t use setattr on object   instances   params     attr1    attr2    attr3   for p in params      setattr obj a  p  value

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The mock module is basically made for that   import mock obj   mock Mock   obj a   5

[python] How can I create an object and add attributes to it?

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