Converting JSON/dict to flatten string with indicator tokens
Given an input like: {'example_id': 0, 'query': ' revent 80 cfm', 'query_id': 0, 'product_id': 'B000MOO21W', 'product_locale': 'us', 'esci_label': 'I', 'small_version': 0, 'large_version': 1, 'split': 'train', 'product_title': 'Panasonic FV-20VQ3 WhisperCeiling 190 CFM Ceiling Mounted Fan', 'product_description': None, 'product_bullet_point': 'WhisperCeiling fans feature…