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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 UnregisterEventHandler(self, Event, Target):
 """Unregisters an event handler previously registered with `RegisterEventHandler`. :Parameters: Event : str Target : callable Callable to unregister. :return: True if callable was successfully unregistered, False if it wasn't registered first. :rtype: bool :see: `RegisterEventHandler` """

        if not callable(Target):
            raise TypeError('%s is not callable' % repr(Target))
        if Event not in self._EventHandlers:
            raise ValueError('%s is not a valid %s event name' % (Event, self.__class__.__name__))
        if Target in self._EventHandlers[Event]:
            self._EventHandlers[Event].remove(Target)
            self.__Logger.info('unregistered %s: %s', Event, repr(Target))
            return True
        return False