code: def receipt(self, msg):
          
          body = msg['body'].replace(NULL, '')
  
          brief_msg = ""
          if 'receipt-id' in msg['headers']:
              brief_msg = msg['headers']['receipt-id']
  
          self.log.info("Received server receipt message - receipt-id:%s\n\n%s" % (brief_msg, body))
  
          returned = NO_RESPONSE_NEEDED
          if self.testing:
              returned = 'receipt'
  
          return returned
docs: Called to handle a receipt message received from the server.
  
          This method just logs the receipt message
  
          returned:
              NO_RESPONSE_NEEDED