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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 bind(self, typevar, its_type):
 """ Binds typevar to the type its_type. Binding occurs on the instance if the typevar is a TypeVar of the generic type of the instance, on call level otherwise. """

        assert type(typevar) == tg.TypeVar
        if self.is_generic_in(typevar):
            self.bind_to_instance(typevar, its_type)
        else:
            self._ns[typevar] = its_type