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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def submit(self, form, url=None, **kwargs):
 """Prepares and sends a form request. NOTE: To submit a form with a :class:`StatefulBrowser` instance, it is recommended to use :func:`StatefulBrowser.submit_selected` instead of this method so that the browser state is correctly updated. :param form: The filled-out form. :param url: URL of the page the form is on. If the form action is a relative path, then this must be specified. :param \\*\\*kwargs: Arguments forwarded to `requests.Session.request <http://docs.python-requests.org/en/master/api/#requests.Session.request>`__. :return: `requests.Response <http://docs.python-requests.org/en/master/api/#requests.Response>`__ object with a *soup*-attribute added by :func:`add_soup`. """

        if isinstance(form, Form):
            form = form.form
        response = self._request(form, url, **kwargs)
        Browser.add_soup(response, self.soup_config)
        return response