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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 _has_example(self, label):
 """Whether this data type has an example with the given ``label``."""

        if label in self._raw_examples:
            return True
        else:
            for field in self.all_fields:
                dt, _ = unwrap_nullable(field.data_type)
                if not is_user_defined_type(dt) and not is_void_type(dt):
                    continue
                if label == field.name:
                    return True
            else:
                return False