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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 array_item_type(type_):
 """returns array item type"""

    if is_array(type_):
        type_ = remove_alias(type_)
        type_ = remove_cv(type_)
        return type_.base
    elif is_pointer(type_):
        return remove_pointer(type_)
    else:
        raise RuntimeError(
            "array_item_type functions takes as argument array or pointer " +
            "types")