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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 get(self, name):
 """Returns a Notification by name. """

        if not self.loaded:
            raise RegistryNotLoaded(self)
        if not self._registry.get(name):
            raise NotificationNotRegistered(
                f"Notification not registered. Got '{name}'."
            )
        return self._registry.get(name)