def test_get_extension(self): f = FFMpeg() audio_extension = f._get_extension('test.aac', 'audio') mp3_extension = f._get_extension('test.mp3', 'audio') video_extension = f._get_extension('test.mp4', 'video') avi_extension = f._get_extension('test.avi', 'video') self.assertEqual(audio_extension, 'aac') self.assertEqual(mp3_extension, 'mp3') self.assertEqual(video_extension, 'mp4') self.assertEqual(avi_extension, 'avi')