def METHOD_NAME(map_file, function_file, argument_file):
    # Decodes the function and its file arguments to be executed into
    # function_code, and updates a user namespace with the function name and
    # the variable named result_name. When the function is executed, its result
    # will be stored in this variable in the user namespace.
    # Returns (namespace, function_code, result_name)
    # Create the namespace to isolate the function execution.
    user_ns = locals()
    user_ns.update({'__builtins__': __builtins__})
    packed_function = load_pickled_file(function_file)
    packed_argument = load_pickled_file(argument_file)
    fn = unpack_object(packed_function, user_ns)
    args_dict = unpack_object(packed_argument, user_ns)
    fn_args = args_dict['args']
    fn_kwargs = args_dict['kwargs']
    fn_name = 'parsl_tmp_func_name'
    mapping = load_pickled_file(map_file)
    remap_all_files(mapping, fn_args, fn_kwargs)
    (code, result_name) = encode_function(user_ns, fn, fn_name, fn_args, fn_kwargs)
    return (user_ns, code, result_name)