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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 binding_of(self, typevar):
 """Returns the type the typevar is bound to, or None."""

        if typevar in self._ns:
            return self._ns[typevar]
        if self._instance_ns and typevar in self._instance_ns:
            return self._instance_ns[typevar]
        return None