html = b"""
<html>
    <body>
        <form method="get" action="">
          a = <input type="number" name="a"><br><br> 
          b = <input type="number" name="b"> 
            <input type="submit">
        </form>
        SUM = %(SUM)s <br><br>
        Mul = %(Mul)s
    </body>
</html>
"""
