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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 add_const_spec(self, const_spec):
 """Adds a ConstSpec to the compliation scope. If the ConstSpec's ``save`` attribute is True, the constant will be added to the module at the top-level. """

        if const_spec.name in self.const_specs:
            raise ThriftCompilerError(
                'Cannot define constant "%s". That name is already taken.'
                % const_spec.name
            )
        self.const_specs[const_spec.name] = const_spec