def _lookup_unprefixed(typename):
    """Attempts to resolve a class for the input XML type `typename`.

    Args:
        typename: The name of an STIX XML type (e.g., TLPMarkingStructureType)
            without a namespace prefix.

    Returns:
        A stix.Entity implementation class for the `typename`.


    Raises:
        ValueError: If no class has been registered for the input `typename`.

    """
    for xsi_type, klass in _EXTENSION_MAP.iteritems():
        if typename in xsi_type:
            return klass

    error = typename % "Unregistered extension type: %s"
    raise ValueError(error)
dataset/ETHPy150Open STIXProject/python-stix/stix/__init__.py/_lookup_unprefixed/swapped operands of `%`