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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:
 async def post(self):
 """ Process POST request if one of handler returns instance of :class:`aiogram.dispatcher.webhook.BaseResponse` return it to webhook. Otherwise do nothing (return 'ok') :return: :class:`aiohttp.web.Response` """

        self.validate_ip()

        # context.update_state({'CALLER': WEBHOOK,
        #                       WEBHOOK_CONNECTION: True,
        #                       WEBHOOK_REQUEST: self.request})

        dispatcher = self.get_dispatcher()
        update = await self.parse_update(dispatcher.bot)

        results = await self.process_update(update)
        response = self.get_response(results)

        if response:
            web_response = response.get_web_response()
        else:
            web_response = web.Response(text='ok')

        if self.request.app.get('RETRY_AFTER', None):
            web_response.headers['Retry-After'] = self.request.app['RETRY_AFTER']

        return web_response