Query: how to check what python libraries i have

Relevant code:
def load_library(version):
    """
    Load the correct module according to the version

    :type version: ``str``
    :param version: the version of the library to be loaded (e.g. '2.6')
    :rtype: module object
    """
    check_version(version)
    module_name = SUPPORTED_LIBRARIES[version]
    lib = sys.modules.get(module_name)
    if lib is None:
        lib = importlib.import_module(module_name)
    return lib

Similar but not relevant code:
def check(modname):
    """Check if required dependency is installed"""
    for dependency in DEPENDENCIES:
        if dependency.modname == modname:
            return dependency.check()
    else:
        raise RuntimeError("Unkwown dependency %s" % modname)

Similar but not relevant code:
def check_dependencies_remote(args):
    """
    Invoke this command on a remote Python.
    """
    cmd = [args.python, '-m', 'depends', args.requirement]
    env = dict(PYTHONPATH=os.path.dirname(__file__))
    return subprocess.check_call(cmd, env=env)

Similar but not relevant code:
def check_python_version():
    """Check if the currently running Python version is new enough."""
    # Required due to multiple with statements on one line
    req_version = (2, 7)
    cur_version = sys.version_info
    if cur_version >= req_version:
        print("Python version... %sOK%s (found %s, requires %s)" %
              (Bcolors.OKGREEN, Bcolors.ENDC, str(platform.python_version()),
               str(req_version[0]) + "." + str(req_version[1])))
    else:
        print("Python version... %sFAIL%s (found %s, requires %s)" %
              (Bcolors.FAIL, Bcolors.ENDC, str(cur_version),
               str(req_version)))

Similar but not relevant code:
def validate_django_compatible_with_python():
    """
    Verify Django 1.11 is present if Python 2.7 is active

    Installation of pinax-cli requires the correct version of Django for
    the active Python version. If the developer subsequently changes
    the Python version the installed Django may no longer be compatible.
    """
    python_version = sys.version[:5]
    django_version = django.get_version()
    if sys.version_info == (2, 7) and django_version >= "2":
        click.BadArgumentUsage("Please install Django v1.11 for Python {}, or switch to Python >= v3.4".format(python_version))

Similar but not relevant code:
def get_versions(reporev=True):
    """Get version information for components used by Spyder"""
    import sys
    import platform

    import qtpy
    import qtpy.QtCore

    revision = None
    if reporev:
        from spyder.utils import vcs
        revision, branch = vcs.get_git_revision(os.path.dirname(__dir__))

    if not sys.platform == 'darwin':  # To avoid a crash with our Mac app
        system = platform.system()
    else:
        system = 'Darwin'

    return {
        'spyder': __version__,
        'python': platform.python_version(),  # "2.7.3"
        'bitness': 64 if sys.maxsize > 2**32 else 32,
        'qt': qtpy.QtCore.__version__,
        'qt_api': qtpy.API_NAME,      # PyQt5
        'qt_api_ver': qtpy.PYQT_VERSION,
        'system': system,   # Linux, Windows, ...
        'release': platform.release(),  # XP, 10.6, 2.2.0, etc.
        'revision': revision,  # '9fdf926eccce'
    }