web2py form creation
===

I'm trying to create a form in web2py. 
I'm not sure on the correct syntax and don't understand from the examples in the site how this is done. Could someone give a better explanation?

How is a simple form like this created?

    <form> 
    <select> 
    <option>Paint</option>
    <option>Brushes</option>
    <option>Erasers</option>
    </select>
    Quantity: <input type="text" /> 
    <input type="submit" />
    </form>

How can I validate more complex forms?

Thanks!
