<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def remove(self, event=None):
 """ Remove all the registered observers for the given event name. Arguments: event (str):
 event name to remove. """

        observers = self._pool.get(event)
        if observers:
            self._pool[event] = []