2 distinct forms

[Cato Nano]

Hello,

I have this piece of code

    def start_requests(self):
        return [FormRequest(url="http://www.blahblah",
                            formdata={'citta':'Lucca'},
                            callback=self.resultList)]

but there are 2 distinct forms in my page

How do I instruct FormRequest to process the right one ?

Thanks in advance