How to print a list in Python nicely

Question

In PHP  I can do this   echo   lt pre gt   print r  array   echo   lt  pre gt     In Python  I currently just do this   print the list   However  this will cause a big jumbo of data  Is there any way to print it nicely into a readable tree   with indents

User · Answer

As the other answers suggest pprint module does the trick   Nonetheless  in case of debugging where you might need to put the entire list into some log file  one might have to use pformat method along with module logging along with pprint   import logging from pprint import pformat  logger   logging getLogger  newlogger   handler   logging FileHandler  newlogger log    formatter   logging Formatter    asctime s   levelname s   message s   handler setFormatter formatter   logger addHandler handler   logger setLevel logging WARNING   data      i     1   one               2   two               3   three               4   four               5   five               6   six               7   seven               8   eight                          for i in xrange 3           logger error pformat data     And if you need to directly log it to a File  one would have to specify an output stream  using the stream keyword  Ref  from pprint import pprint  with open  output txt    wt   as out     pprint myTree  stream out    See Stefano Sanfilippo s answer

User · Answer

A quick hack while debugging that works without having to import pprint would be to join the list on   n     gt  gt  gt  lst     foo    bar    spam    egg    gt  gt  gt  print   n  join lst  foo bar spam egg

User · Answer

You mean something like       gt  gt  gt  print L   this    is    a     and    a    sublist    too     list    including    many    words    in    it    gt  gt  gt  import pprint  gt  gt  gt  pprint pprint L    this     is     a      and    a    sublist    too      list     including     many     words     in     it    gt  gt  gt           From your cursory description  standard library module pprint is the first thing that comes to mind  however  if you can describe example inputs and outputs  so that one doesn t have to learn PHP in order to help you -   it may be possible for us to offer more specific help

User · Answer

Simply by  unpacking  the list in the print function argument and using a newline   n  as separator   print  lst  sep   n    lst     foo    bar    spam    egg   print  lst  sep   n    foo bar spam egg

User · Answer

import json some list     one    two    three    four   print json dumps some list  indent 4     Output          one        two        three        four

User · Answer

https   docs python org 3 library pprint html  If you need the text  for using with curses for example    import pprint  myObject       myText   pprint pformat myObject    Then myText variable will something alike php var dump or print r  Check the documentation for more options  arguments

User · Answer

you can also loop trough your list   def fun      for i in x      print i   x     1  1  a  8  fun

User · Answer

This is a method from raw python that I use very often  The code looks like this  list     quot a quot    quot b quot    quot c quot    quot d quot    quot e quot    quot f quot    quot g quot    for i in range len list        print list i    output  a b c d e f g

User · Answer

As other answers have mentioned  pprint is a great module that will do what you want  However if you don t want to import it and just want to print debugging output during development  you can approximate its output   Some of the other answers work fine for strings  but if you try them with a class object it will give you the error TypeError  sequence item 0  expected string  instance found    For more complex objects  make sure the class has a   repr   method that prints the property information you want   class Foo object       def   init   self  bar           self bar   bar      def   repr   self           return  Foo -   r     self bar   And then when you want to print the output  simply map your list to the str function like this   l    Foo 10   Foo 20   Foo  A string    Foo 2 4   print    s        n   join map str l     outputs     Foo -  10     Foo -  20     Foo -   A string      Foo -  2 4     You can also do things like override the   repr   method of list to get a form of nested pretty printing   class my list list       def   repr   self           return    s        n   join map str  self    a   my list   first   2  my list   another    list    here      last    print a   gives   first   2    another   list   here    last    Unfortunately no second-level indentation but for a quick debug it can be useful

User · Answer

from pprint import pprint pprint the list

User · Answer

For Python 3  I do the same kind of thing as shxfee s answer   def print list my list       print   n  join my list    a     foo    bar    baz   print list a    which outputs  foo bar baz   As an aside  I use a similar helper function to quickly see columns in a pandas DataFrame  def print cols df       print   n  join df columns

[python] How to print a list in Python "nicely"

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