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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 invalidate(self, assoc_handle, dumb):
 """Invalidates the association with the given handle. @type assoc_handle: str @param dumb: Is this association used with dumb mode? @type dumb: bool """

        if dumb:
            key = self._dumb_key
        else:
            key = self._normal_key
        self.store.removeAssociation(key, assoc_handle)