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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def request(self, action):
 """Request an action to be performed, in case one."""

    ev = threading.Event()
    first = False
    with self.__lock:
      if len(self.__events) == 0:
        first = True
      self.__events.append(ev)
    if first:
      action()
    return ev