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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 remove_observer(self, signal, observer):
 """Remove an observer from the object. Raise an eception if the signal is not allowed. Parameters signal : str a valid signal. observer : @func an obervation function to be removed. """


        self._is_allowed_event(signal)
        self._remove_observer(signal, observer)