def process(self, expression):
a, o, b = expression<EOL>c1 = self._hextorgb(a)<EOL>c2 = self._hextorgb(b)<EOL>r = ['<STR_LIT:#>']<EOL>for i in range(<NUM_LIT:3>):<EOL><INDENT>v = self.operate(c1[i], c2[i], o)<EOL>if v > <NUM_LIT>:<EOL><INDENT>v = <NUM_LIT><EOL><DEDENT>if v < <NUM_LIT:0>:<EOL><INDENT>v = <NUM_LIT:0><EOL><DEDENT>r.append("<STR_LIT>" % int(v))<EOL><DEDENT>return '<STR_LIT>'.join(r)<EOL>
Process color expression
        args:
            expression (tuple): color expression
        returns:
            str