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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 unusedAssignments(self):
 """Return a generator for the assignments which have not been used."""

        for name, binding in self.items():
            if (not binding.used and name not in self.globals
                    and not self.uses_locals
                    and isinstance(binding, Assignment)):
                yield name, binding