code: def do_execute(self):
          
          fname = str(self.input.payload)
          spattern = str(self.resolve_option("regexp"))
          pattern = None
          if (spattern is not None) and (spattern != ".*"):
              pattern = re.compile(spattern)
          if (pattern is None) or (pattern.match(fname)):
              os.remove(fname)
          self._output.append(self.input)
          return None
docs: The actual execution of the actor.
  
          :return: None if successful, otherwise error message
          :rtype: str