"pprint" — Data pretty printer
******************************

**Source code:** Lib/pprint.py

======================================================================

The "pprint" module provides a capability to “pretty-print” arbitrary
Python data structures in a form which can be used as input to the
interpreter. If the formatted structures include objects which are not
fundamental Python types, the representation may not be loadable.
This may be the case if objects such as files, sockets or classes are
included, as well as many other objects which are not representable as
Python literals.

The formatted representation keeps objects on a single line if it can,
and breaks them onto multiple lines if they don’t fit within the
allowed width, adjustable by the *width* parameter defaulting to 80
characters.

Changed in version 3.9: Added support for pretty-printing
"types.SimpleNamespace".

Changed in version 3.10: Added support for pretty-printing
"dataclasses.dataclass".


Functions
=========

pprint.pp(object, stream=None, indent=1, width=80, depth=None, *, compact=False, sort_dicts=False, underscore_numbers=False)

   Prints the formatted representation of *object*, followed by a
   newline. This function may be used in the interactive interpreter
   instead of the "print()" function for inspecting values. Tip: you
   can reassign "print = pprint.pp" for use within a scope.

   Parameters:
      * **object** – The object to be printed.

      * **stream** (*file-like object* | None) – A file-like object to
        which the output will be written by calling its "write()"
        method. If "None" (the default), "sys.stdout" is used.

      * **indent** (*int*) – The amount of indentation added for each
        nesting level.

      * **width** (*int*) – The desired maximum number of characters
        per line in the output. If a structure cannot be formatted
        within the width constraint, a best effort will be made.

      * **depth** (*int** | **None*) – The number of nesting levels
        which may be printed. If the data structure being printed is
        too deep, the next contained level is replaced by "...". If
        "None" (the default), there is no constraint on the depth of
        the objects being formatted.

      * **compact** (*bool*) – Control the way long *sequences* are
        formatted. If "False" (the default), each item of a sequence
        will be formatted on a separate line, otherwise as many items
        as will fit within the *width* will be formatted on each
        output line.

      * **sort_dicts** (*bool*) – If "True", dictionaries will be
        formatted with their keys sorted, otherwise they will be
        displayed in insertion order (the default).

      * **underscore_numbers** (*bool*) – If "True", integers will be
        formatted with the "_" character for a thousands separator,
        otherwise underscores are not displayed (the default).

   >>> import pprint
   >>> stuff = ['spam', 'eggs', 'lumberjack', 'knights', 'ni']
   >>> stuff.insert(0, stuff)
   >>> pprint.pp(stuff)
   [<Recursion on list with id=...>,
    'spam',
    'eggs',
    'lumberjack',
    'knights',
    'ni']

   Added in version 3.8.

pprint.pprint(object, stream=None, indent=1, width=80, depth=None, *, compact=False, sort_dicts=True, underscore_numbers=False)

   Alias for "pp()" with *sort_dicts* set to "True" by default, which
   would automatically sort the dictionaries’ keys, you might want to
   use "pp()" instead where it is "False" by default.

pprint.pformat(object, indent=1, width=80, depth=None, *, compact=False, sort_dicts=True, underscore_numbers=False)

   Return the formatted representation of *object* as a string.
   *indent*, *width*, *depth*, *compact*, *sort_dicts* and
   *underscore_numbers* are passed to the "PrettyPrinter" constructor
   as formatting parameters and their meanings are as described in the
   documentation above.

pprint.isreadable(object)

   Determine if the formatted representation of *object* is
   “readable”, or can be used to reconstruct the value using "eval()".
   This always returns "False" for recursive objects.

   >>> pprint.isreadable(stuff)
   False

pprint.isrecursive(object)

   Determine if *object* requires a recursive representation.  This
   function is subject to the same limitations as noted in
   "saferepr()" below and may raise an "RecursionError" if it fails to
   detect a recursive object.

pprint.saferepr(object)

   Return a string representation of *object*, protected against
   recursion in some common data structures, namely instances of
   "dict", "list" and "tuple" or subclasses whose "__repr__" has not
   been overridden.  If the representation of object exposes a
   recursive entry, the recursive reference will be represented as
   "<Recursion on typename with id=number>".  The representation is
   not otherwise formatted.

   >>> pprint.saferepr(stuff)
   "[<Recursion on list with id=...>, 'spam', 'eggs', 'lumberjack', 'knights', 'ni']"


PrettyPrinter Objects
=====================

class pprint.PrettyPrinter(indent=1, width=80, depth=None, stream=None, *, compact=False, sort_dicts=True, underscore_numbers=False)

   Construct a "PrettyPrinter" instance.

   Arguments have the same meaning as for "pp()". Note that they are
   in a different order, and that *sort_dicts* defaults to "True".

   >>> import pprint
   >>> stuff = ['spam', 'eggs', 'lumberjack', 'knights', 'ni']
   >>> stuff.insert(0, stuff[:])
   >>> pp = pprint.PrettyPrinter(indent=4)
   >>> pp.pprint(stuff)
   [   ['spam', 'eggs', 'lumberjack', 'knights', 'ni'],
       'spam',
       'eggs',
       'lumberjack',
       'knights',
       'ni']
   >>> pp = pprint.PrettyPrinter(width=41, compact=True)
   >>> pp.pprint(stuff)
   [['spam', 'eggs', 'lumberjack',
     'knights', 'ni'],
    'spam', 'eggs', 'lumberjack', 'knights',
    'ni']
   >>> tup = ('spam', ('eggs', ('lumberjack', ('knights', ('ni', ('dead',
   ... ('parrot', ('fresh fruit',))))))))
   >>> pp = pprint.PrettyPrinter(depth=6)
   >>> pp.pprint(tup)
   ('spam', ('eggs', ('lumberjack', ('knights', ('ni', ('dead', (...)))))))

   Changed in version 3.4: Added the *compact* parameter.

   Changed in version 3.8: Added the *sort_dicts* parameter.

   Changed in version 3.10: Added the *underscore_numbers* parameter.

   Changed in version 3.11: No longer attempts to write to
   "sys.stdout" if it is "None".

"PrettyPrinter" instances have the following methods:

PrettyPrinter.pformat(object)

   Return the formatted representation of *object*.  This takes into
   account the options passed to the "PrettyPrinter" constructor.

PrettyPrinter.pprint(object)

   Print the formatted representation of *object* on the configured
   stream, followed by a newline.

The following methods provide the implementations for the
corresponding functions of the same names.  Using these methods on an
instance is slightly more efficient since new "PrettyPrinter" objects
don’t need to be created.

PrettyPrinter.isreadable(object)

   Determine if the formatted representation of the object is
   “readable,” or can be used to reconstruct the value using "eval()".
   Note that this returns "False" for recursive objects.  If the
   *depth* parameter of the "PrettyPrinter" is set and the object is
   deeper than allowed, this returns "False".

PrettyPrinter.isrecursive(object)

   Determine if the object requires a recursive representation.

This method is provided as a hook to allow subclasses to modify the
way objects are converted to strings.  The default implementation uses
the internals of the "saferepr()" implementation.

PrettyPrinter.format(object, context, maxlevels, level)

   Returns three values: the formatted version of *object* as a
   string, a flag indicating whether the result is readable, and a
   flag indicating whether recursion was detected.  The first argument
   is the object to be presented.  The second is a dictionary which
   contains the "id()" of objects that are part of the current
   presentation context (direct and indirect containers for *object*
   that are affecting the presentation) as the keys; if an object
   needs to be presented which is already represented in *context*,
   the third return value should be "True".  Recursive calls to the
   "format()" method should add additional entries for containers to
   this dictionary.  The third argument, *maxlevels*, gives the
   requested limit to recursion; this will be "0" if there is no
   requested limit.  This argument should be passed unmodified to
   recursive calls. The fourth argument, *level*, gives the current
   level; recursive calls should be passed a value less than that of
   the current call.


Example
=======

To demonstrate several uses of the "pp()" function and its parameters,
let’s fetch information about a project from PyPI:

   >>> import json
   >>> import pprint
   >>> from urllib.request import urlopen
   >>> with urlopen('https://pypi.org/pypi/sampleproject/1.2.0/json') as resp:
   ...     project_info = json.load(resp)['info']

In its basic form, "pp()" shows the whole object:

   >>> pprint.pp(project_info)
   {'author': 'The Python Packaging Authority',
    'author_email': 'pypa-dev@googlegroups.com',
    'bugtrack_url': None,
    'classifiers': ['Development Status :: 3 - Alpha',
                    'Intended Audience :: Developers',
                    'License :: OSI Approved :: MIT License',
                    'Programming Language :: Python :: 2',
                    'Programming Language :: Python :: 2.6',
                    'Programming Language :: Python :: 2.7',
                    'Programming Language :: Python :: 3',
                    'Programming Language :: Python :: 3.2',
                    'Programming Language :: Python :: 3.3',
                    'Programming Language :: Python :: 3.4',
                    'Topic :: Software Development :: Build Tools'],
    'description': 'A sample Python project\n'
                   '=======================\n'
                   '\n'
                   'This is the description file for the project.\n'
                   '\n'
                   'The file should use UTF-8 encoding and be written using '
                   'ReStructured Text. It\n'
                   'will be used to generate the project webpage on PyPI, and '
                   'should be written for\n'
                   'that purpose.\n'
                   '\n'
                   'Typical contents for this file would include an overview of '
                   'the project, basic\n'
                   'usage examples, etc. Generally, including the project '
                   'changelog in here is not\n'
                   'a good idea, although a simple "What\'s New" section for the '
                   'most recent version\n'
                   'may be appropriate.',
    'description_content_type': None,
    'docs_url': None,
    'download_url': 'UNKNOWN',
    'downloads': {'last_day': -1, 'last_month': -1, 'last_week': -1},
    'home_page': 'https://github.com/pypa/sampleproject',
    'keywords': 'sample setuptools development',
    'license': 'MIT',
    'maintainer': None,
    'maintainer_email': None,
    'name': 'sampleproject',
    'package_url': 'https://pypi.org/project/sampleproject/',
    'platform': 'UNKNOWN',
    'project_url': 'https://pypi.org/project/sampleproject/',
    'project_urls': {'Download': 'UNKNOWN',
                     'Homepage': 'https://github.com/pypa/sampleproject'},
    'release_url': 'https://pypi.org/project/sampleproject/1.2.0/',
    'requires_dist': None,
    'requires_python': None,
    'summary': 'A sample Python project',
    'version': '1.2.0'}

The result can be limited to a certain *depth* (ellipsis is used for
deeper contents):

   >>> pprint.pp(project_info, depth=1)
   {'author': 'The Python Packaging Authority',
    'author_email': 'pypa-dev@googlegroups.com',
    'bugtrack_url': None,
    'classifiers': [...],
    'description': 'A sample Python project\n'
                   '=======================\n'
                   '\n'
                   'This is the description file for the project.\n'
                   '\n'
                   'The file should use UTF-8 encoding and be written using '
                   'ReStructured Text. It\n'
                   'will be used to generate the project webpage on PyPI, and '
                   'should be written for\n'
                   'that purpose.\n'
                   '\n'
                   'Typical contents for this file would include an overview of '
                   'the project, basic\n'
                   'usage examples, etc. Generally, including the project '
                   'changelog in here is not\n'
                   'a good idea, although a simple "What\'s New" section for the '
                   'most recent version\n'
                   'may be appropriate.',
    'description_content_type': None,
    'docs_url': None,
    'download_url': 'UNKNOWN',
    'downloads': {...},
    'home_page': 'https://github.com/pypa/sampleproject',
    'keywords': 'sample setuptools development',
    'license': 'MIT',
    'maintainer': None,
    'maintainer_email': None,
    'name': 'sampleproject',
    'package_url': 'https://pypi.org/project/sampleproject/',
    'platform': 'UNKNOWN',
    'project_url': 'https://pypi.org/project/sampleproject/',
    'project_urls': {...},
    'release_url': 'https://pypi.org/project/sampleproject/1.2.0/',
    'requires_dist': None,
    'requires_python': None,
    'summary': 'A sample Python project',
    'version': '1.2.0'}

Additionally, maximum character *width* can be suggested. If a long
object cannot be split, the specified width will be exceeded:

   >>> pprint.pp(project_info, depth=1, width=60)
   {'author': 'The Python Packaging Authority',
    'author_email': 'pypa-dev@googlegroups.com',
    'bugtrack_url': None,
    'classifiers': [...],
    'description': 'A sample Python project\n'
                   '=======================\n'
                   '\n'
                   'This is the description file for the '
                   'project.\n'
                   '\n'
                   'The file should use UTF-8 encoding and be '
                   'written using ReStructured Text. It\n'
                   'will be used to generate the project '
                   'webpage on PyPI, and should be written '
                   'for\n'
                   'that purpose.\n'
                   '\n'
                   'Typical contents for this file would '
                   'include an overview of the project, '
                   'basic\n'
                   'usage examples, etc. Generally, including '
                   'the project changelog in here is not\n'
                   'a good idea, although a simple "What\'s '
                   'New" section for the most recent version\n'
                   'may be appropriate.',
    'description_content_type': None,
    'docs_url': None,
    'download_url': 'UNKNOWN',
    'downloads': {...},
    'home_page': 'https://github.com/pypa/sampleproject',
    'keywords': 'sample setuptools development',
    'license': 'MIT',
    'maintainer': None,
    'maintainer_email': None,
    'name': 'sampleproject',
    'package_url': 'https://pypi.org/project/sampleproject/',
    'platform': 'UNKNOWN',
    'project_url': 'https://pypi.org/project/sampleproject/',
    'project_urls': {...},
    'release_url': 'https://pypi.org/project/sampleproject/1.2.0/',
    'requires_dist': None,
    'requires_python': None,
    'summary': 'A sample Python project',
    'version': '1.2.0'}
