What Does the python -v Command Do

Question

I recently reinstalled my macOS and I wanted to check the version of Python. I typed python -v into the terminal and I am not sure what this did? I am new to the terminal and python programming. Did I install new software on accident?

Last login: Sun May 14 15:02:37 on ttys000
Matthews-MacBook-Pro:~ matthewkol$ python -v
# installing zipimport hook
import zipimport # builtin
# installed zipimport hook
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site.py
import site # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/os.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/os.py
import os # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/os.pyc
import errno # builtin
import posix # builtin
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/posixpath.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/posixpath.py
import posixpath # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/posixpath.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/stat.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/stat.py
import stat # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/stat.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/genericpath.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/genericpath.py
import genericpath # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/genericpath.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/warnings.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/warnings.py
import warnings # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/warnings.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/linecache.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/linecache.py
import linecache # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/linecache.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/types.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/types.py
import types # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/types.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/UserDict.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/UserDict.py
import UserDict # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/UserDict.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_abcoll.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_abcoll.py
import _abcoll # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_abcoll.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/abc.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/abc.py
import abc # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/abc.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_weakrefset.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_weakrefset.py
import _weakrefset # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_weakrefset.pyc
import _weakref # builtin
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/copy_reg.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/copy_reg.py
import copy_reg # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/copy_reg.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/traceback.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/traceback.py
import traceback # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/traceback.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sysconfig.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sysconfig.py
import sysconfig # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sysconfig.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/re.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/re.py
import re # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/re.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sre_compile.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sre_compile.py
import sre_compile # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sre_compile.pyc
import _sre # builtin
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sre_parse.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sre_parse.py
import sre_parse # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sre_parse.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sre_constants.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sre_constants.py
import sre_constants # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sre_constants.pyc
dlopen("/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/_locale.so", 2);
import _locale # dynamically loaded from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/_locale.so
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_sysconfigdata.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_sysconfigdata.py
import _sysconfigdata # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_sysconfigdata.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_osx_support.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_osx_support.py
import _osx_support # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/_osx_support.pyc
import encodings # directory /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/__init__.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/__init__.py
import encodings # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/__init__.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/codecs.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/codecs.py
import codecs # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/codecs.pyc
import _codecs # builtin
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/aliases.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/aliases.py
import encodings.aliases # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/aliases.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/utf_8.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/utf_8.py
import encodings.utf_8 # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/encodings/utf_8.pyc
Python 2.7.10 (default, Feb  6 2017, 23:53:20) 
[GCC 4.2.1 Compatible Apple LLVM 8.0.0 (clang-800.0.34)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
dlopen("/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/readline.so", 2);
import readline # dynamically loaded from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/readline.so
>>> help
Type help() for interactive help, or help(object) for help about object.
>>> help(object)
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pydoc.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pydoc.py
import pydoc # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pydoc.pyc
import imp # builtin
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/inspect.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/inspect.py
import inspect # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/inspect.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/string.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/string.py
import string # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/string.pyc
dlopen("/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/strop.so", 2);
import strop # dynamically loaded from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/strop.so
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/dis.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/dis.py
import dis # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/dis.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/opcode.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/opcode.py
import opcode # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/opcode.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/tokenize.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/tokenize.py
import tokenize # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/tokenize.pyc
dlopen("/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/itertools.so", 2);
import itertools # dynamically loaded from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/itertools.so
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/token.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/token.py
import token # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/token.pyc
dlopen("/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/operator.so", 2);
import operator # dynamically loaded from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/operator.so
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/collections.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/collections.py
import collections # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/collections.pyc
dlopen("/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/_collections.so", 2);
import _collections # dynamically loaded from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/_collections.so
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/keyword.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/keyword.py
import keyword # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/keyword.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/heapq.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/heapq.py
import heapq # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/heapq.pyc
dlopen("/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/_heapq.so", 2);
import _heapq # dynamically loaded from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/_heapq.so
import thread # builtin
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pkgutil.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pkgutil.py
import pkgutil # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pkgutil.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/repr.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/repr.py
import repr # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/repr.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/locale.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/locale.py
import locale # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/locale.pyc
# /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.pyc matches /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.py
import functools # precompiled from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/functools.pyc
dlopen("/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/_functools.so", 2);
import _functools # dynamically loaded from /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload/_functools.so

>>> python -V
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'python' is not defined
>>> exit
Use exit() or Ctrl-D (i.e. EOF) to exit
>>> ^D
# clear __builtin__._
# clear sys.path
# clear sys.argv
# clear sys.ps1
# clear sys.ps2
# clear sys.exitfunc
# clear sys.exc_type
# clear sys.exc_value
# clear sys.exc_traceback
# clear sys.last_type
# clear sys.last_value
# clear sys.last_traceback
# clear sys.path_hooks
# clear sys.path_importer_cache
# clear sys.meta_path
# clear sys.flags
# clear sys.float_info
# restore sys.stdin
# restore sys.stdout
# restore sys.stderr
# cleanup __main__
# cleanup[1] _collections
# cleanup[1] site
# cleanup[1] sysconfig
# cleanup[1] _heapq
# cleanup[1] abc
# cleanup[1] _weakrefset
# cleanup[1] sre_constants
# cleanup[1] collections
# cleanup[1] _codecs
# cleanup[1] opcode
# cleanup[1] _warnings
# cleanup[1] _sysconfigdata
# cleanup[1] repr
# cleanup[1] _osx_support
# cleanup[1] readline
# cleanup[1] strop
# cleanup[1] _functools
# cleanup[1] thread
# cleanup[1] keyword
# cleanup[1] signal
# cleanup[1] traceback
# cleanup[1] pydoc
# cleanup[1] itertools
# cleanup[1] posix
# cleanup[1] exceptions
# cleanup[1] _weakref
# cleanup[1] token
# cleanup[1] heapq
# cleanup[1] locale
# cleanup[1] functools
# cleanup[1] encodings
# cleanup[1] operator
# cleanup[1] pkgutil
# cleanup[1] zipimport
# cleanup[1] inspect
# cleanup[1] encodings.utf_8
# cleanup[1] imp
# cleanup[1] codecs
# cleanup[1] encodings.aliases
# cleanup[1] dis
# cleanup[1] tokenize
# cleanup[1] string
# cleanup[1] re
# cleanup[1] _locale
# cleanup[1] sre_compile
# cleanup[1] _sre
# cleanup[1] sre_parse
# cleanup[2] copy_reg
# cleanup[2] posixpath
# cleanup[2] errno
# cleanup[2] _abcoll
# cleanup[2] types
# cleanup[2] genericpath
# cleanup[2] stat
# cleanup[2] warnings
# cleanup[2] UserDict
# cleanup[2] os.path
# cleanup[2] linecache
# cleanup[2] os
# cleanup sys
# cleanup __builtin__
# cleanup ints: 21 unfreed ints
# cleanup floats
Matthews-MacBook-Pro:~ matthewkol$ 

Solution 1

This will show you the way your modules are loading for debugging reasons. (in this case it is just the base modules)

Documentation: https://docs.python.org/2/using/cmdline.html#cmdoption-v

Solution 2

You didn't do anything wrong. From the man page for Python (accessed by man python):

   -v     Print  a  message each time a module is initialized, showing the
          place (filename or built-in module) from  which  it  is  loaded.
          When  given twice, print a message for each file that is checked
          for when searching for a module.  Also provides  information  on
          module cleanup at exit.

   -V ,  --version
          Prints  the  Python  version number of the executable and exits.
          When given twice, print more information about the build.

Think of the lowercase -v as "verbose"—it's useful for debugging modules. The modules you listed are all from the standard library.

Comments

[idjaw]

Per the official documentation - docs.python.org/3/using/cmdline.html#cmdoption-v. You are using Python 2, but for this particular case it doesn't matter, but here is the py2 doc

[idjaw]

You want to use an upper case v for the version. There is a difference between lower case v and upper case v when passing parameters to the python command.

[Matthew]

To make sure I understand correctly, I've imported Python so that I can write Python scripts within the terminal itself? and then when I quit it clears everything out and cleans it up? Also, what exactly occurs when it says it is clearing and cleaning?

[Menachem Hornbacher]

Yes. That is what is happening