code: def from_mapping(cls, evidence_mapping):
          
          return cls(metadata_map=MetadataMap.from_mapping(evidence_mapping['metadataMap']),
                     copyright=evidence_mapping['copyright'],
                     id=evidence_mapping['id'],
                     terms_of_use=evidence_mapping['termsOfUse'],
                     document=evidence_mapping['document'],
                     title=evidence_mapping['title'],
                     text=evidence_mapping['text'],
                     value=evidence_mapping['value'])
docs: Create an Evidence instance from the given mapping
  
          :param evidence_mapping: a mapping (e.g. dict) of values provided by Watson
          :return: a new Evidence