def METHOD_NAME(minimal_swagger_spec):
    response_spec = {
        'description': 'I return an int',
        'schema': {
            'type': 'integer',
        },
    }
    op = Operation(
        minimal_swagger_spec, '/foo', 'get',
        op_spec={'produces': ['application/xml']},
    )
    response = Mock(spec=OutgoingResponse, content_type='application/xml')
    with pytest.raises(SwaggerMappingError) as excinfo:
        validate_response_body(op, response_spec, response)
    assert 'Unsupported content-type' in str(excinfo.value)