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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 hook_inform(self, inform_name, callback):
 """Hookup a function to be called when an inform is received. Useful for interface-changed and sensor-status informs. Parameters inform_name : str The name of the inform. callback : function The function to be called. """

        # Do not hook the same callback multiple times
        if callback not in self._inform_hooks[inform_name]:
            self._inform_hooks[inform_name].append(callback)