17. Binary to Gray Code Converter

How do you plan to solve it?

module bin2gray4(
    input [3:0] bin_in,
    output [3:0]gray_out
);
assign {gray_out[3],gray_out[2],gray_out[1],gray_out[0]} = {bin_in[3],bin_in[3]^bin_in[2],bin_in[2]^bin_in[1],bin_in[1]^bin_in[0]};
endmodule