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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 request(self):
        '''Perform the Http request to the upstream server
        '''
        request_headers = self.request_headers()
        environ = self.environ
        method = environ['REQUEST_METHOD']
        data = None
        if method in ENCODE_BODY_METHODS:
            data = DataIterator(self)
        http = self.wsgi.http_client
        try:
            await http.request(method,
                               environ['RAW_URI'],
                               data=data,
                               headers=request_headers,
                               version=environ['SERVER_PROTOCOL'],
                               pre_request=self.pre_request)
        except Exception as exc:
            self.error(exc)