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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 create_decl_string( return_type, arguments_types, with_defaults=True):
 """ Returns free function type :param return_type: function return type :type return_type: :class:`type_t` :param arguments_types: list of argument :class:`type <type_t>` :rtype: :class:`free_function_type_t` """


        return free_function_type_t.NAME_TEMPLATE % {
            'return_type': return_type.build_decl_string(with_defaults),
            'arguments': ','.join(
                [_f(x, with_defaults) for x in arguments_types])}