You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: flip.m
    path of file: ./repos/SuiteSparse/GraphBLAS/GraphBLAS/@GrB
    
    the code of the file until where you have to start completion: function C = flip (A, dim)
%FLIP flip the order of elements.
% C = flip (A) flips the order of elements in each column of A.  That is,
% C = A (end:-1:1,:).  C = flip (A, dim) specifies the dimension to flip
    
function on a built-in matrix, use C = flip (A, GrB (dim)).
%
% See also GrB/transpose.

% SuiteSparse:GraphBLAS, Timothy A. Davis, (c) 2017-2023, All Rights Reserved.
% SPDX-License-Identifier: Apache-2.0

a_is_object = isobject (A) ;
if (a_is_object)
    G = A.opaque ;
else
    G = A ;
end