Question: who sings with lady gaga in just dance
[{'answer': "Colby O'Donis", 'provenance': [{'wikipedia_id': '18097249', 'title': 'Just Dance (song)', 'start_paragraph_id': 1, 'start_character': 149, 'end_paragraph_id': 1, 'end_character': 162, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '18097249', 'title': 'Just Dance (song)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 418, 'bleu_score': 0.6970841655313501, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7728853047462138308}, 'section': 'Section::::Abstract.'}]}]