def _luminance(self, rgb):
a = []<EOL>for v in rgb:<EOL><INDENT>v = v / float(<NUM_LIT:255>)<EOL>if v < <NUM_LIT>:<EOL><INDENT>result = v / <NUM_LIT><EOL><DEDENT>else:<EOL><INDENT>result = math.pow(((v + <NUM_LIT>) / <NUM_LIT>), <NUM_LIT>)<EOL><DEDENT>a.append(result)<EOL><DEDENT>return a[<NUM_LIT:0>] * <NUM_LIT> + a[<NUM_LIT:1>] * <NUM_LIT> + a[<NUM_LIT:2>] * <NUM_LIT><EOL>
Determine the liminanace of an RGB colour