'Returns True if every form in self.forms is valid.'

def is_valid(self):

    if (not self.is_bound):
        return False
    forms_valid = True
    err = self.errors
    for i in range(0, self.total_form_count()):
        form = self.forms[i]
        if self.can_delete:
            if self._should_delete_form(form):
                continue
        forms_valid &= form.is_valid()
    return (forms_valid and (not bool(self.non_form_errors())))
