python html form library that supports forms within form (form as a field )?

The question says it all,

For example,

In a contact book if someone has multiple addresses with each address having multiple fields I want to display an "add another address"开发者_JS百科 button. This button would add another address form. (I want one round trip to the server, I do not want javascript or webforms2.)

It would be nice if some built in library would support this. Examples are appreciated.

Thanks.

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Try django-formsets, and if you want dynamic behavior use this http://code.google.com/p/django-dynamic-formset/