'Ensure that ids that are invalid return an empty dict'

def test_parse_youtube_invalid(self):

    youtube_str = 'thisisaninvalidid'
    output = VideoDescriptor._parse_youtube(youtube_str)
    self.assertEqual(output, {'0.75': '', '1.00': '', '1.25': '', '1.50': ''})
    youtube_str = ',::,:,,'
    output = VideoDescriptor._parse_youtube(youtube_str)
    self.assertEqual(output, {'0.75': '', '1.00': '', '1.25': '', '1.50': ''})
    youtube_str = '0.75_BAD!!!,1.0:AXdE34_U,1.25:KLHF9K_Y,1.5:VO3SxfeD,'
    output = VideoDescriptor._parse_youtube(youtube_str)
    self.assertEqual(output, {'0.75': '', '1.00': 'AXdE34_U', '1.25': 'KLHF9K_Y', '1.50': 'VO3SxfeD'})
