Question: what is upper case and lower case character
[{'answer': 'Letter case', 'provenance': [{'wikipedia_id': '625125', 'title': 'Letter case', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 11, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '625125', 'title': 'Letter case', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 700, 'bleu_score': 0.9486604584788991, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10433532891374423268}, 'section': 'Section::::Abstract.'}]}]