Question: who sings number 4 song on sesame street
[{'answer': 'Leslie Feist', 'provenance': [{'wikipedia_id': '1539839', 'title': 'Feist (singer)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 12, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1539839', 'title': 'Feist (singer)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 186, 'bleu_score': 0.7981256013410021, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8824067015880999273}, 'section': 'Section::::Abstract.'}]}]