code: def parse(self, subscription):
          
  
          for name in self.methods:
              tag = bytes(name.encode('utf-8'))
              if subscription.startswith(tag):
                  fun = self.methods.get(name)
                  message = subscription[len(tag):]
                  return tag, message, fun
          return None, None, None
docs: Fetch the function registered for a certain subscription