I would like to get a list of Python modules, which are in my Python installation (UNIX server).
How can you get a list of Python modules installed in your computer?
My 50 cents for getting a pip freeze-like list from a Python script:
import pip
installed_packages = pip.get_installed_distributions()
installed_packages_list = sorted(["%s==%s" % (i.key, i.version)
     for i in installed_packages])
print(installed_packages_list)
As a (too long) one liner:
sorted(["%s==%s" % (i.key, i.version) for i in pip.get_installed_distributions()])
Giving:
['behave==1.2.4', 'enum34==1.0', 'flask==0.10.1', 'itsdangerous==0.24', 
 'jinja2==2.7.2', 'jsonschema==2.3.0', 'markupsafe==0.23', 'nose==1.3.3', 
 'parse-type==0.3.4', 'parse==1.6.4', 'prettytable==0.7.2', 'requests==2.3.0',
 'six==1.6.1', 'vioozer-metadata==0.1', 'vioozer-users-server==0.1', 
 'werkzeug==0.9.4']
This solution applies to the system scope or to a virtual environment scope, and covers packages installed by setuptools, pip and (god forbid) easy_install.
I added the result of this call to my flask server, so when I call it with http://example.com/exampleServer/environment I get the list of packages installed on the server's virtualenv. It makes debugging a whole lot easier.
I have noticed a strange behaviour of this technique - when the Python interpreter is invoked in the same directory as a setup.py file, it does not list the package installed by setup.py.
$ cd /tmp
$ virtualenv test_env
New python executable in test_env/bin/python
Installing setuptools, pip...done.
$ source test_env/bin/activate
(test_env) $ 
setup.py(test_env) $ git clone https://github.com/behave/behave.git
Cloning into 'behave'...
remote: Reusing existing pack: 4350, done.
remote: Total 4350 (delta 0), reused 0 (delta 0)
Receiving objects: 100% (4350/4350), 1.85 MiB | 418.00 KiB/s, done.
Resolving deltas: 100% (2388/2388), done.
Checking connectivity... done.
We have behave's setup.py in /tmp/behave:
(test_env) $ ls /tmp/behave/setup.py
/tmp/behave/setup.py
(test_env) $ cd /tmp/behave && pip install . 
running install
...
Installed /private/tmp/test_env/lib/python2.7/site-packages/enum34-1.0-py2.7.egg
Finished processing dependencies for behave==1.2.5a1
/tmp>>> import pip
>>> sorted(["%s==%s" % (i.key, i.version) for i in pip.get_installed_distributions()])
['behave==1.2.5a1', 'enum34==1.0', 'parse-type==0.3.4', 'parse==1.6.4', 'six==1.6.1']
>>> import os
>>> os.getcwd()
'/private/tmp'
/tmp/behave>>> import pip
>>> sorted(["%s==%s" % (i.key, i.version) for i in pip.get_installed_distributions()])
['enum34==1.0', 'parse-type==0.3.4', 'parse==1.6.4', 'six==1.6.1']
>>> import os
>>> os.getcwd()
'/private/tmp/behave'
behave==1.2.5a1 is missing from the second example, because the working directory contains behave's setup.py file.
I could not find any reference to this issue in the documentation. Perhaps I shall open a bug for it.
Now, these methods I tried myself, and I got exactly what was advertised: All the modules.
Alas, really you don't care much about the stdlib, you know what you get with a python install.
Really, I want the stuff that I installed.
What actually, surprisingly, worked just fine was:
pip freeze
Which returned:
Fabric==0.9.3
apache-libcloud==0.4.0
bzr==2.3b4
distribute==0.6.14
docutils==0.7
greenlet==0.3.1
ipython==0.10.1
iterpipes==0.4
libxml2-python==2.6.21
I say "surprisingly" because the package install tool is the exact place one would expect to find this functionality, although not under the name 'freeze' but python packaging is so weird, that I am flabbergasted that this tool makes sense. Pip 0.8.2, Python 2.7.
Since pip version 1.3, you've got access to:
pip list
Which seems to be syntactic sugar for "pip freeze". It will list all of the modules particular to your installation or virtualenv, along with their version numbers. Unfortunately it does not display the current version number of any module, nor does it wash your dishes or shine your shoes.
In ipython you can type "importTab".
In the standard Python interpreter, you can type "help('modules')".
At the command-line, you can use pydoc modules.
In a script, call pkgutil.iter_modules().
As of pip 10, the accepted answer will no longer work.  The development team has removed access to the get_installed_distributions routine.  There is an alternate function in the setuptools for doing the same thing.  Here is an alternate version that works with pip 10:
import pkg_resources
installed_packages = pkg_resources.working_set
installed_packages_list = sorted(["%s==%s" % (i.key, i.version)
     for i in installed_packages])
print(installed_packages_list)
Please let me know if it will or won't work in previous versions of pip, too.
Run the following in your python editor or IPython:
import pkg_resources
installed_packages = {d.project_name: d.version for d in pkg_resources.working_set}
print(installed_packages)
Read other answers and pulled together this combo, which is quickest and easiest inside Python.
Conveniently you can then get items from your dict easily, i.e.
installed_packages['pandas'] >> '1.16.4'
!pip list will run inside your jupyter notebook if working there, simplifying the 'quick check'
Combine with other utilities like grep(if you have installed)
pip list | grep pandas  will get you your current pandas version for example
I normally use pip list to get a list of packages (with version).
This works in a virtual environment too, of course. To show what's installed in only the virtual environment (not global packages), use pip list --local.
Here's documentation showing all the available pip list options, with several good examples.
In terminal or IPython, type:
help('modules')
then
In [1]: import                      #import press-TAB
Display all 631 possibilities? (y or n)
ANSI                   audiodev               markupbase
AptUrl                 audioop                markupsafe
ArgImagePlugin         avahi                  marshal
BaseHTTPServer         axi                    math
Bastion                base64                 md5
BdfFontFile            bdb                    mhlib
BmpImagePlugin         binascii               mimetools
BufrStubImagePlugin    binhex                 mimetypes
CDDB                   bisect                 mimify
CDROM                  bonobo                 mmap
CGIHTTPServer          brlapi                 mmkeys
Canvas                 bsddb                  modulefinder
CommandNotFound        butterfly              multifile
ConfigParser           bz2                    multiprocessing
ContainerIO            cPickle                musicbrainz2
Cookie                 cProfile               mutagen
Crypto                 cStringIO              mutex
CurImagePlugin         cairo                  mx
DLFCN                  calendar               netrc
DcxImagePlugin         cdrom                  new
Dialog                 cgi                    nis
DiscID                 cgitb                  nntplib
DistUpgrade            checkbox               ntpath
Very simple searching using pkgutil.iter_modules
from pkgutil import iter_modules
a=iter_modules()
while True:
    try: x=a.next()
    except: break
    if 'searchstr' in x[1]: print x[1]
I ran into a custom installed python 2.7 on OS X. It required X11 to list modules installed (both using help and pydoc).
To be able to list all modules without installing X11 I ran pydoc as http-server, i.e.:
pydoc -p 12345
Then it's possible to direct Safari to http://localhost:12345/ to see all modules.
This solution is primary based on modules importlib and pkgutil and work with CPython 3.4 and CPython 3.5, but has no support for the CPython 2.
Explanation
sys.builtin_module_names - names all built-in modules (look my answer here)pkgutil.iter_modules() - returns an information about all available modulesimportlib.util.find_spec() - returns an information about importing module, if existsBuiltinImporter - an importer for built-in modules (docs)SourceFileLoader - an importer for a standard Python module (by default has extension *.py) (docs)ExtensionFileLoader - an importer for modules as shared library (written on the C or C++)Full code
import sys
import os
import shutil
import pkgutil
import importlib
import collections
if sys.version_info.major == 2:
    raise NotImplementedError('CPython 2 is not supported yet')
def main():
    # name this file (module)
    this_module_name = os.path.basename(__file__).rsplit('.')[0]
    # dict for loaders with their modules
    loaders = collections.OrderedDict()
    # names`s of build-in modules
    for module_name in sys.builtin_module_names:
        # find an information about a module by name
        module = importlib.util.find_spec(module_name)
        # add a key about a loader in the dict, if not exists yet
        if module.loader not in loaders:
            loaders[module.loader] = []
        # add a name and a location about imported module in the dict
        loaders[module.loader].append((module.name, module.origin))
    # all available non-build-in modules
    for module_name in pkgutil.iter_modules():
        # ignore this module
        if this_module_name == module_name[1]:
            continue
        # find an information about a module by name
        module = importlib.util.find_spec(module_name[1])
        # add a key about a loader in the dict, if not exists yet
        loader = type(module.loader)
        if loader not in loaders:
            loaders[loader] = []
        # add a name and a location about imported module in the dict
        loaders[loader].append((module.name, module.origin))
    # pretty print
    line = '-' * shutil.get_terminal_size().columns
    for loader, modules in loaders.items():
        print('{0}\n{1}: {2}\n{0}'.format(line, len(modules), loader))
        for module in modules:
            print('{0:30} | {1}'.format(module[0], module[1]))
if __name__ == '__main__':
    main()
Usage
For the CPython3.5 (truncated)
$ python3.5 python_modules_info.py 
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30: <class '_frozen_importlib.BuiltinImporter'>
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
_ast                           | built-in
_codecs                        | built-in
_collections                   | built-in
_functools                     | built-in
_imp                           | None
_io                            | built-in
_locale                        | built-in
_operator                      | built-in
_signal                        | built-in
_sre                           | built-in
_stat                          | built-in
_string                        | built-in
_symtable                      | built-in
_thread                        | built-in
(****************************truncated*******************************)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
227: <class '_frozen_importlib_external.SourceFileLoader'>
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
__future__                     | /usr/local/lib/python3.5/__future__.py
_bootlocale                    | /usr/local/lib/python3.5/_bootlocale.py
_collections_abc               | /usr/local/lib/python3.5/_collections_abc.py
_compat_pickle                 | /usr/local/lib/python3.5/_compat_pickle.py
_compression                   | /usr/local/lib/python3.5/_compression.py
_dummy_thread                  | /usr/local/lib/python3.5/_dummy_thread.py
_markupbase                    | /usr/local/lib/python3.5/_markupbase.py
_osx_support                   | /usr/local/lib/python3.5/_osx_support.py
_pydecimal                     | /usr/local/lib/python3.5/_pydecimal.py
_pyio                          | /usr/local/lib/python3.5/_pyio.py
_sitebuiltins                  | /usr/local/lib/python3.5/_sitebuiltins.py
(****************************truncated*******************************)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
64: <class '_frozen_importlib_external.ExtensionFileLoader'>
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
_bisect                        | /usr/local/lib/python3.5/lib-dynload/_bisect.cpython-35m-x86_64-linux-gnu.so
_bz2                           | /usr/local/lib/python3.5/lib-dynload/_bz2.cpython-35m-x86_64-linux-gnu.so
_codecs_cn                     | /usr/local/lib/python3.5/lib-dynload/_codecs_cn.cpython-35m-x86_64-linux-gnu.so
_codecs_hk                     | /usr/local/lib/python3.5/lib-dynload/_codecs_hk.cpython-35m-x86_64-linux-gnu.so
_codecs_iso2022                | /usr/local/lib/python3.5/lib-dynload/_codecs_iso2022.cpython-35m-x86_64-linux-gnu.so
(****************************truncated*******************************)
For the CPython3.4 (truncated)
$ python3.4 python_modules_info.py
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
54: <class '_frozen_importlib.BuiltinImporter'>
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
_ast                           | built-in
_bisect                        | built-in
_codecs                        | built-in
_collections                   | built-in
_datetime                      | built-in
_elementtree                   | built-in
_functools                     | built-in
_heapq                         | built-in
_imp                           | None
_io                            | built-in
_locale                        | built-in
_md5                           | built-in
_operator                      | built-in
_pickle                        | built-in
_posixsubprocess               | built-in
_random                        | built-in
(****************************truncated*******************************)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
246: <class '_frozen_importlib.SourceFileLoader'>
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
__future__                     | /usr/lib/python3.4/__future__.py
_bootlocale                    | /usr/lib/python3.4/_bootlocale.py
_collections_abc               | /usr/lib/python3.4/_collections_abc.py
_compat_pickle                 | /usr/lib/python3.4/_compat_pickle.py
_dummy_thread                  | /usr/lib/python3.4/_dummy_thread.py
_markupbase                    | /usr/lib/python3.4/_markupbase.py
_osx_support                   | /usr/lib/python3.4/_osx_support.py
_pyio                          | /usr/lib/python3.4/_pyio.py
(****************************truncated*******************************)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
44: <class '_frozen_importlib.ExtensionFileLoader'>
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
_bz2                           | /usr/lib/python3.4/lib-dynload/_bz2.cpython-34m-x86_64-linux-gnu.so
_codecs_cn                     | /usr/lib/python3.4/lib-dynload/_codecs_cn.cpython-34m-x86_64-linux-gnu.so
_codecs_hk                     | /usr/lib/python3.4/lib-dynload/_codecs_hk.cpython-34m-x86_64-linux-gnu.so
_codecs_iso2022                | /usr/lib/python3.4/lib-dynload/_codecs_iso2022.cpython-34m-x86_64-linux-gnu.so
_codecs_jp                     | /usr/lib/python3.4/lib-dynload/_codecs_jp.cpython-34m-x86_64-linux-gnu.so
_codecs_kr                     | /usr/lib/python3.4/lib-dynload/_codecs_kr.cpython-34m-x86_64-linux-gnu.so
_codecs_tw                     | /usr/lib/python3.4/lib-dynload/_codecs_tw.cpython-34m-x86_64-linux-gnu.so
_crypt                         | /usr/lib/python3.4/lib-dynload/_crypt.cpython-34m-x86_64-linux-gnu.so
(****************************truncated*******************************)
Warning: Adam Matan discourages this use in pip > 10.0. Also, read @sinoroc's comment below
This was inspired by Adam Matan's answer (the accepted one):
import tabulate
try:
  from pip import get_installed_distributions
except:
  from pip._internal.utils.misc import get_installed_distributions
tabpackages = []
for _, package in sorted([('%s %s' % (i.location, i.key), i) for i in get_installed_distributions()]):
  tabpackages.append([package.location, package.key, package.version])
print(tabulate.tabulate(tabpackages))
which then prints out a table in the form of
19:33 pi@rpi-v3 [iot-wifi-2] ~/python$ python installed_packages.py
-------------------------------------------  --------------  ------
/home/pi/.local/lib/python2.7/site-packages  enum-compat     0.0.2
/home/pi/.local/lib/python2.7/site-packages  enum34          1.1.6
/home/pi/.local/lib/python2.7/site-packages  pexpect         4.2.1
/home/pi/.local/lib/python2.7/site-packages  ptyprocess      0.5.2
/home/pi/.local/lib/python2.7/site-packages  pygatt          3.2.0
/home/pi/.local/lib/python2.7/site-packages  pyserial        3.4
/usr/local/lib/python2.7/dist-packages       bluepy          1.1.1
/usr/local/lib/python2.7/dist-packages       click           6.7
/usr/local/lib/python2.7/dist-packages       click-datetime  0.2
/usr/local/lib/python2.7/dist-packages       construct       2.8.21
/usr/local/lib/python2.7/dist-packages       pyaudio         0.2.11
/usr/local/lib/python2.7/dist-packages       tabulate        0.8.2
-------------------------------------------  --------------  ------
which lets you then easily discern which packages you installed with and without sudo.
A note aside: I've noticed that when I install a packet once via sudo and once without, one takes precedence so that the other one isn't being listed (only one location is shown). I believe that only the one in the local directory is then listed. This could be improved.
In case you have an anaconda python distribution installed, you could also use
$conda list
in addition to solutions described above.
sys.modulespip), you may look at pip.get_installed_distributions()For the second purpose, example code:
import pip
for package in pip.get_installed_distributions():
    name = package.project_name # SQLAlchemy, Django, Flask-OAuthlib
    key = package.key # sqlalchemy, django, flask-oauthlib
    module_name = package._get_metadata("top_level.txt") # sqlalchemy, django, flask_oauthlib
    location = package.location # virtualenv lib directory etc.
    version = package.version # version number
There are many way to skin a cat.
The most simple way is to use the pydoc function directly from the shell with:pydoc modules
But for more information use the tool called pip-date that also tell you the installation dates.pip install pip-date
There are many ideas, initially I am pondering on these two:
pip
cons: not always installed
help('modules')
cons: output to console; with broken modules (see ubuntu...) can segfault
I need an easy approach, using basic libraries and compatible with old python 2.x
And I see the light: listmodules.py
Hidden in the documentation source directory in 2.5 is a small script that lists all available modules for a Python installation.
Pros:
uses only imp, sys, os, re, time
designed to run on Python 1.5.2 and newer
the source code is really compact, so you can easy tinkering with it, for example to pass an exception list of buggy modules (don't try to import them)
I needed to find the specific version of packages available by default in AWS Lambda. I did so with a mashup of ideas from this page. I'm sharing it for posterity.
import pkgutil
__version__ = '0.1.1'
def get_ver(name):
    try:
        return str(__import__(name).__version__)
    except:
        return None
def lambda_handler(event, context):
    return {
        'statusCode': 200,
        'body': [{
                   'path': m.module_finder.path,
                   'name': m.name,
                   'version': get_ver(m.name),
                 } for m in list(pkgutil.iter_modules())
                 #if m.module_finder.path == "/var/runtime" # Uncomment this if you only care about a certain path
                ],
    }
What I discovered is that the provided boto3 library was way out of date and it wasn't my fault that my code was failing. I just needed to add boto3 and botocore to my project. But without this I would have been banging my head thinking my code was bad.
{
  "statusCode": 200,
  "body": [
    {
      "path": "/var/task",
      "name": "lambda_function",
      "version": "0.1.1"
    },
    {
      "path": "/var/runtime",
      "name": "bootstrap",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "boto3",
      "version": "1.9.42"
    },
    {
      "path": "/var/runtime",
      "name": "botocore",
      "version": "1.12.42"
    },
    {
      "path": "/var/runtime",
      "name": "dateutil",
      "version": "2.7.5"
    },
    {
      "path": "/var/runtime",
      "name": "docutils",
      "version": "0.14"
    },
    {
      "path": "/var/runtime",
      "name": "jmespath",
      "version": "0.9.3"
    },
    {
      "path": "/var/runtime",
      "name": "lambda_runtime_client",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "lambda_runtime_exception",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "lambda_runtime_marshaller",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "s3transfer",
      "version": "0.1.13"
    },
    {
      "path": "/var/runtime",
      "name": "six",
      "version": "1.11.0"
    },
    {
      "path": "/var/runtime",
      "name": "test_bootstrap",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "test_lambda_runtime_client",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "test_lambda_runtime_marshaller",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "urllib3",
      "version": "1.24.1"
    },
    {
      "path": "/var/lang/lib/python3.7",
      "name": "__future__",
      "version": null
    },
...
What I discovered was also different from what they officially publish. At the time of writing this:
- Operating system – Amazon Linux
- AMI – amzn-ami-hvm-2017.03.1.20170812-x86_64-gp2
- Linux kernel – 4.14.77-70.59.amzn1.x86_64
- AWS SDK for JavaScript – 2.290.0\
- SDK for Python (Boto 3) – 3-1.7.74 botocore-1.10.74
Here is a python code solution that will return a list of modules installed. One can easily modify the code to include version numbers.
import subprocess
import sys
from pprint import pprint
installed_packages = reqs = subprocess.check_output([sys.executable, '-m', 'pip', 'freeze']).decode('utf-8')
installed_packages = installed_packages.split('\r\n')
installed_packages = [pkg.split('==')[0] for pkg in installed_packages if pkg != '']
pprint(installed_packages)
If none of the above seem to help, in my environment was broken from a system upgrade and I could not upgrade pip. While it won't give you an accurate list you can get an idea of which libraries were installed simply by looking inside your env>lib>python(version here)>site-packages> . Here you will get a good indication of modules installed.
pip list? - H Aßdøµpython3 -c "help('modules')"- sodimel