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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 _check_type(self):
 """Check that point value types match the descriptor type."""

        check_type = metric_descriptor.MetricDescriptorType.to_type_class(
            self.descriptor.type)
        for ts in self.time_series:
            if not ts.check_points_type(check_type):
                raise ValueError("Invalid point value type")