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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 as_symbols(self):
 """Set of symbols required by this Require :return: set of ``(symbol type, symbol name)`` tuples """

        out = set()
        for name in self.types:
            out.add(('type', name))
        for name in self.enums:
            out.add(('enum', name))
        for name in self.commands:
            out.add(('command', name))
        return out