Question: who played the role of karna in mahabharata
[{'answer': 'Pankaj Dheer', 'provenance': [{'wikipedia_id': '7353278', 'title': 'Mahabharat (1988 TV series)', 'start_paragraph_id': 28, 'start_character': 12, 'end_paragraph_id': 28, 'end_character': 24, 'bleu_score': 1.0, 'section': 'Section::::Cast.:Main.\n'}]}, {'provenance': [{'wikipedia_id': '7353278', 'title': 'Mahabharat (1988 TV series)', 'start_paragraph_id': 28, 'start_character': 36, 'end_paragraph_id': 28, 'end_character': 114, 'bleu_score': 0.56591192566527, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16910412771598748965}, 'section': 'Section::::Cast.:Main.\n'}]}]