Question: what is money as a medium of exchange
[{'answer': 'fiat money', 'provenance': [{'wikipedia_id': '313793', 'title': 'Medium of exchange', 'start_paragraph_id': 2, 'start_character': 117, 'end_paragraph_id': 2, 'end_character': 127, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'a tradeable entity used to avoid the inconveniences of a pure barter system'}, {'provenance': [{'wikipedia_id': '313793', 'title': 'Medium of exchange', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 0, 'bleu_score': 1.0, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13533673421811017150}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '313793', 'title': 'Medium of exchange', 'start_paragraph_id': 28, 'start_character': 0, 'end_paragraph_id': 28, 'end_character': 1128, 'bleu_score': 0.9898215517422001, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13533673421811017150}, 'section': 'Section::::Medium of Exchange and Measure of Value.\n'}]}, {'provenance': [{'wikipedia_id': '22156522', 'title': 'Fiat money', 'section': 'Section::::History.:New France 1685–1770.\n', 'start_paragraph_id': 24, 'end_paragraph_id': 24, 'meta': {'evidence_span': ['Fiat money also has other roots in 17th-century Europe, having been introduced by the Bank of Amsterdam in 1683. In 17th century New France, now part of Canada, the universally accepted medium of exchange was the beaver pelt', 'Fiat money']}}]}, {'provenance': [{'wikipedia_id': '313793', 'title': 'Medium of exchange', 'section': 'Section::::Abstract.', 'start_paragraph_id': 2, 'end_paragraph_id': 2, 'meta': {'evidence_span': ['fiat money', 'Most forms of money can act as mediums of exchange including commodity money, representative money and most commonly fiat money. Representative and fiat money often exist in digital form as well as physical tokens such as coins and notes.']}}]}]