How to use the wagtailmedia.__version__ function in wagtailmedia

'mock>=1.0.0',

    # For coverage and PEP8 linting
    'coverage>=3.7.0',
    'flake8>=2.2.0',

    # Required for matrix build on Travis
    'tox==3.9.0',
]

with io.open('README.md', encoding='utf-8') as readme_file:
    long_description = readme_file.read()

setup(
    name='wagtailmedia',
    version=__version__,
    description='A module for Wagtail that provides functionality '
                'similar to wagtail.documents module, but for audio and video files.',
    author='Mikalai Radchuk',
    author_email='mikalai.radchuk@torchbox.com',
    url='https://github.com/torchbox/wagtailmedia',
    packages=find_packages(),
    include_package_data=True,
    license='BSD',
    long_description=long_description,
    long_description_content_type='text/markdown',
    classifiers=[
        'Development Status :: 4 - Beta',
        'Environment :: Web Environment',
        'Intended Audience :: Developers',
        'License :: OSI Approved :: BSD License',
        'Operating System :: OS Independent',