Type help() in the interpreter
then
To get a list of available modules, keywords, or topics, type "modules",
"keywords", or "topics". Each module also comes with a one-line summary
of what it does; to list the modules whose summaries contain a given word
such as "spam", type "modules spam".
help> modules
Type help() in the interpreter
then
To get a list of available modules, keywords, or topics, type "modules",
"keywords", or "topics". Each module also comes with a one-line summary
of what it does; to list the modules whose summaries contain a given word
such as "spam", type "modules spam".
help> modules
If you use ipython, which is an improved interactive Python shell (aka "REPL"), you can type import (note the space at the end) followed by a press of the [TAB] key to get a list of importable modules.
As noted in this SO post, you will have to reset its hash of modules after installing (certain?) new ones. You likely don't need to worry about this yet.
If you don't use ipython, and you haven't tried it, it might be worth checking out. It's a lot better than the basic Python shell, or pretty much any other REPL I've used.
ipython Installation
If you're running linux, there is most likely an ipython package that you can install through your system management tools. Others will want to follow these instructions.
If your installation route requires you to use easy_install, you may want to consider instead using pip. pip is a bit smarter than easy_install and does a better job of keeping track of file locations. This is very helpful if you end up wanting to uninstall ipython.
Listing packages
Note that the above tip only lists modules. For a list which also includes packages —which contain modules— you can do from + [TAB]. An explanation of the difference between packages and modules can be found in the Modules chapter of the helpful official Python tutorial.
#rtfm
As an added note, if you are very new to python, your time may be better spent browsing the standard library documentation than by just selecting modules based on their name. Python's core documentation is well-written and well-organized. The organizational groups —File and Directory Access, Data Types, etc.— used in the library documentation's table of contents are not readily apparent from the module/package names, and are not really used elsewhere, but serve as a valuable learning aid.
Some solutions are calling help('modules') and using a command line. But I want a list (the list structure) of all available imports. How can I do this?
Actually, what I’m trying to do is explore what libraries are available on Pythonista 3 (an iOS Python IDE). I want to get a list of modules excluding those from the standard library so I can print out each module’s docstring.
python - How to list imported modules? - Stack Overflow
How do I get a list of locally installed Python modules? - Stack Overflow
Is there a standard way to list names of Python modules in a package? - Stack Overflow
Easy way to list classes/functions defined in module without importing it?
Perhaps this will help
https://pypi.python.org/pypi/astdump/4.2
Extract information from Python modules without importing
Even with this I think you're going to have a tough time getting what you want, as things can be defined in a module dynamically such that they don't exist as "plain names" until the module is executed/imported
More on reddit.comimport sys
sys.modules.keys()
An approximation of getting all imports for the current module only would be to inspect globals() for modules:
import types
def imports():
for name, val in globals().items():
if isinstance(val, types.ModuleType):
yield val.__name__
This won't return local imports, or non-module imports like from x import y. Note that this returns val.__name__ so you get the original module name if you used import module as alias; yield name instead if you want the alias.
Find the intersection of sys.modules with globals:
import sys
modulenames = set(sys.modules) & set(globals())
allmodules = [sys.modules[name] for name in modulenames]
help('modules')
in a Python shell/prompt.
Solution
Do not use with pip > 10.0!
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']
Scope
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.
My use case
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.
Caveats
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.
Steps to reproduce:
Create a virtual environment
virtualenv test_env
New python executable in test_env/bin/python
Installing setuptools, pip...done.
$ source test_env/bin/activate
(test_env) $
Clone a Git repository with 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
Install the Python package from the Git repository
(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
If we run the aforementioned solution from /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'
If we run the aforementioned solution from /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.
Using python2.3 and above, you could also use the pkgutil module:
>>> import pkgutil
>>> [name for _, name, _ in pkgutil.iter_modules(['testpkg'])]
['modulea', 'moduleb']
EDIT: Note that the parameter for pkgutil.iter_modules is not a list of modules, but a list of paths, so you might want to do something like this:
>>> import os.path, pkgutil
>>> import testpkg
>>> pkgpath = os.path.dirname(testpkg.__file__)
>>> print([name for _, name, _ in pkgutil.iter_modules([pkgpath])])
import module
help(module)