def METHOD_NAME(app):
    """Install the plugin.
    :param app: Sphinx application context.
    """
    app.info('Initializing GitHub plugin')
    app.add_role('ghissue', ghissue_role)
    app.add_role('ghpull', ghissue_role)
    app.add_role('ghuser', ghuser_role)
    app.add_role('ghcommit', ghcommit_role)
    app.add_config_value('github_project_url', None, 'env')
    return