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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 delete_metadata(self, href=None):
 """Delete metadata. 'href' the relative href to the bundle. May not be None. Returns nothing. If the response status is not 204, throws an APIException."""


        # Argument error checking.
        assert href is not None

        raw_result = self.delete(href)

        if raw_result.status != 204:
            raise APIException(raw_result.status, raw_result.json)