code: def if_match(self):
          
          value = []
          for option in self.options:
              if option.number == defines.OptionRegistry.IF_MATCH.number:
                  value.append(option.value)
          return value
docs: Get the If-Match option of a request.
  
          :return: the If-Match values or [] if not specified by the request
          :rtype : list