Question: when did the philadelphia eagles enter the nfl
[{'answer': '1933', 'provenance': [{'wikipedia_id': '2898735', 'title': 'History of the Philadelphia Eagles', 'start_paragraph_id': 1, 'start_character': 49, 'end_paragraph_id': 1, 'end_character': 53, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2898735', 'title': 'History of the Philadelphia Eagles', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 752, 'bleu_score': 0.9839344367380701, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17361522746646681911}, 'section': 'Section::::Beginnings (1933-39).:Formation and Early Years.\n'}]}]