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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 ListOf(element_type, element_none_value=None):
 """ This function creates a list type with element type ``element_type`` and an empty element value ``element_none_value``. True 'IntegerList' True """

    from pyws.functions.args.types import TypeFactory
    element_type = TypeFactory(element_type)
    return type(element_type.__name__ + 'List', (List,), {
        'element_type': element_type,
        'element_none_value': element_none_value})