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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 global_symbols_in_children(self):
 """ This is based on all children referenced symbols that have not been declared. The intended use case is to ban the symbols from being used as remapped symbol values. """


        result = set()
        for child in self.children:
            result |= (
                child.global_symbols |
                child.global_symbols_in_children)
        return result