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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 container_elem_type(container_type, params):
 """ Returns container element type :param container_type: :param params: :return: """

    elem_type = params[0] if params else None
    if elem_type is None:
        elem_type = container_type.ELEM_TYPE
    return elem_type