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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 register_reference(self, dispatcher, node):
 """ Register this identifier to the current scope, and mark it as referenced in the current scope. """


        # the identifier node itself will be mapped to the current scope
        # for the resolve to work
        # This should probably WARN about the node object being already
        # assigned to an existing scope that isn't current_scope.
        self.identifiers[node] = self.current_scope
        self.current_scope.reference(node.value)