You can use pkg_resources:

import pkg_resourcesdef get_pkg_license(pkgname):    """    Given a package reference (as from requirements.txt),    return license listed in package metadata.    NOTE: This function does no error checking and is for    demonstration purposes only.    """    pkgs = pkg_resources.require(pkgname)    pkg = pkgs[0]    for line in pkg.get_metadata_lines('PKG-INFO'):        (k, v) = line.split(': ', 1)        if k == "License":            return v    return None

Example use:

>>> get_pkg_license('mercurial')'GNU GPLv2+'>>> get_pkg_license('pytz')'MIT'>>> get_pkg_license('django')'UNKNOWN'

Here is a copy-pasteable snippet which will print your packages.

Requires: prettytable (pip install prettytable)

Code

import pkg_resourcesimport prettytabledef get_pkg_license(pkg):    try:        lines = pkg.get_metadata_lines('METADATA')    except:        lines = pkg.get_metadata_lines('PKG-INFO')    for line in lines:        if line.startswith('License:'):            return line[9:]    return '(Licence not found)'def print_packages_and_licenses():    t = prettytable.PrettyTable(['Package', 'License'])    for pkg in sorted(pkg_resources.working_set, key=lambda x: str(x).lower()):        t.add_row((str(pkg), get_pkg_license(pkg)))    print(t)if __name__ == "__main__":    print_packages_and_licenses()

Example Output

+---------------------------+--------------------------------------------------------------+|          Package          |                           License                            |+---------------------------+--------------------------------------------------------------+|       appdirs 1.4.3       |                             MIT                              ||     argon2-cffi 16.3.0    |                             MIT                              ||        boto3 1.4.4        |                      Apache License 2.0                      ||      botocore 1.5.21      |                      Apache License 2.0                      ||        cffi 1.10.0        |                             MIT                              ||       colorama 0.3.9      |                             BSD                              ||      decorator 4.0.11     |                       new BSD License                        ||        Django 1.11        |                             BSD                              ||  django-debug-toolbar 1.7 |                             BSD                              ||    django-environ 0.4.3   |                         MIT License                          ||   django-storages 1.5.2   |                             BSD                              ||    django-uuslug 1.1.8    |                             BSD                              || djangorestframework 3.6.2 |                             BSD                              ||      docutils 0.13.1      | public domain, Python, 2-Clause BSD, GPL 3 (see COPYING.txt) ||     EasyProcess 0.2.3     |                             BSD                              ||       ipython 6.0.0       |                             BSD                              ||   ipython-genutils 0.2.0  |                             BSD                              ||        jedi 0.10.2        |                             MIT                              ||       jmespath 0.9.1      |                             MIT                              ||       packaging 16.8      |              BSD or Apache License, Version 2.0              ||     pickleshare 0.7.4     |                             MIT                              ||         pip 9.0.1         |                             MIT                              ||     prettytable 0.7.2     |                        BSD (3 clause)                        ||   prompt-toolkit 1.0.14   |                           UNKNOWN                            ||       psycopg2 2.6.2      |                 LGPL with exceptions or ZPL                  ||       pycparser 2.17      |                             BSD                              ||       Pygments 2.2.0      |                         BSD License                          ||      pyparsing 2.2.0      |                         MIT License                          ||   python-dateutil 2.6.0   |                        Simplified BSD                        ||    python-slugify 1.2.4   |                             MIT                              ||        pytz 2017.2        |                             MIT                              ||   PyVirtualDisplay 0.2.1  |                             BSD                              ||     s3transfer 0.1.10     |                      Apache License 2.0                      ||       selenium 3.0.2      |                           UNKNOWN                            ||     setuptools 35.0.2     |                           UNKNOWN                            ||    simplegeneric 0.8.1    |                           ZPL 2.1                            ||         six 1.10.0        |                             MIT                              ||       sqlparse 0.2.3      |                             BSD                              ||      traitlets 4.3.2      |                             BSD                              ||      Unidecode 0.4.20     |                             GPL                              ||       wcwidth 0.1.7       |                             MIT                              ||       wheel 0.30.0a0      |                             MIT                              ||  win-unicode-console 0.5  |                             MIT                              |+---------------------------+--------------------------------------------------------------+

Here is a way to do this with yolk3k (Command-line tool for querying PyPI and Python packages installed on your system.)

pip install yolk3kyolk -l -f license#-l lists all installed packages#-f Show specific metadata fields (In this case, License)