Code in verilog a 7 segment LED decoder. (use hex characters)

I have the test bench made already

module Lab4Test;

reg [3:0] num;

wire [6:0] segment;

integer file;

LEDDecoder LD( segment, num);

initial begin num = 4'b0000;

file = $fopen(\"hw03.txt\");

repeat (16) begin #1 $fdisplay(file,\"input = %b Segments 0 = %b, 1 = %b, 2 = %b, 3 = %b 4 = %b 5 = %b 6 = %b\", num, segment[0], segment[1], segment[2], segment[3], segment[4], segment[5], segment[6]);

// LED display $fwrite(file, \" \"); if( segment[6] == 1) $fwrite(file, \"_\");

$fwrite(file, \" \");

if( segment[1] == 1) $fwrite(file, \"|\"); else $fwrite(file, \" \"); if( segment[0] == 1) $fwrite(file, \"_\"); else $fwrite(file, \" \"); if( segment[5] == 1) $fwrite(file, \"|\"); else $fwrite(file, \" \");

$fwrite(file, \" \");

if( segment[2] == 1) $fwrite(file, \"|\");

else $fwrite(file, \" \"); if( segment[3] == 1) $fwrite(file, \"_\"); else $fwrite(file, \" \"); if( segment[4] == 1) $fwrite(file, \"|\"); else $fwrite(file, \" \");

$fwrite(file, \" \");

#10 num = num + 1'b1;

end

end

endmodule