def METHOD_NAME(service_model, filename):
    dirname, filename = os.path.split(filename)
    basename = os.path.splitext(filename)[0]
    sn, opname = basename.split('-', 1)
    # In order to have multiple tests for the same
    # operation a '#' char is used to separate
    # operation names from some other suffix so that
    # the tests have a different filename, e.g
    # my-operation#1.xml, my-operation#2.xml.
    opname = opname.split('#')[0]
    operation_names = service_model.operation_names
    for operation_name in operation_names:
        if xform_name(operation_name) == opname.replace('-', '_'):
            return service_model.operation_model(operation_name)