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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 _handle_response(self):
 """ Handles response after the redirect to GitHub. This response determines if the user has allowed the this application access. If we were then we send a POST request for the access_key used to authenticate requests to GitHub. """

        _logger.debug("Handling response from GitHub")
        params = {
            'code': request.args.get('code'),
            'client_id': self.client_id,
            'client_secret': self.client_secret
        }
        url = self.auth_url + 'access_token'
        _logger.debug("POSTing to %s", url)
        _logger.debug(params)
        response = self.session.post(url, data=params)
        data = parse_qs(response.content)
        _logger.debug("response.content = %s", data)
        for k, v in data.items():
            if len(v) == 1:
                data[k] = v[0]
        token = data.get(b'access_token', None)
        if token is not None:
            token = token.decode('ascii')
        return token