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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 remove_alias(type_):
 """ Returns `type_t` without typedef Args: type_ (type_t | declaration_t):
 type or declaration Returns: type_t: the type associated to the inputted declaration """

    if isinstance(type_, cpptypes.type_t):
        type_ref = type_
    elif isinstance(type_, typedef.typedef_t):
        type_ref = type_.decl_type
    else:
        # Not a valid input, just return it
        return type_
    if type_ref.cache.remove_alias:
        return type_ref.cache.remove_alias
    no_alias = __remove_alias(type_ref.clone())
    type_ref.cache.remove_alias = no_alias
    return no_alias