[web2py] Paypal Digital Download

[Andrew Evans]

Hello! I am working on a project that requires a Digital Download where the
download is provided after the payment has been sent to paypal.

The documentation on Paypal in web2py is very confusing and I don't know if
its for the purpose of what I need. I am generating a paypal/button for
express checkout. and I am trying to think of ways I can then redirect the
user to a page where they can download the product

Normally this would be simpler but I have multiple people selling there
different products and with that multiple products

here is my paypal code

<br /><br />
<form name="_xclick" action="https://www.paypal.com/cgi-bin/webscr";
method="post">
<input type="hidden" name="cmd" value="_xclick">
<input type="hidden" name="business"
value="{{=db.auth_user[row.userinfo].email}}">
<input type="hidden" name="currency_code"
value="{{=db.currency_paypal[row.currency].current}}">
<input type="hidden" name="item_name" value="{{=row.product_name}}">
<input type="hidden" name="no_shipping" value="1">
<input type="hidden" name="custom" value="{{=row.id}}">
<input type="hidden" name="amount" value="{{='%.2f'%float(row.price)}}">
<input type="hidden" name="return" value="" />
<input type="hidden" name="cancel_return" value=""/>
<input type="image" src="http://www.paypal.com/en_US/i/btn/btn_buynow_SM.gif";
border="0" name="submit" alt="Make payments with PayPal - it's fast, free
and secure!">
</form>

So my question is: How can I use paypal for a digital download using the
express checkout button? Do I need to create an IPN class and add notify_url
to my paypal code if so can some one provide an example

*cheers

and ty

Andrew