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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 _construct_event(flask_request, port, binary_types):
 """ Helper method that constructs the Event to be passed to Lambda :param request flask_request: Flask Request :return: String representing the event """


        identity = ContextIdentity(source_ip=flask_request.remote_addr)

        endpoint = PathConverter.convert_path_to_api_gateway(flask_request.endpoint)
        method = flask_request.method

        request_data = flask_request.get_data()

        request_mimetype = flask_request.mimetype

        is_base_64 = LocalApigwService._should_base64_encode(binary_types, request_mimetype)

        if is_base_64:
            LOG.debug("Incoming Request seems to be binary. Base64 encoding the request data before sending to Lambda.")
            request_data = base64.b64encode(request_data)

        if request_data:
            # Flask does not parse/decode the request data. We should do it ourselves
            request_data = request_data.decode('utf-8')

        context = RequestContext(resource_path=endpoint,
                                 http_method=method,
                                 stage="prod",
                                 identity=identity,
                                 path=endpoint)

        event_headers = dict(flask_request.headers)
        event_headers["X-Forwarded-Proto"] = flask_request.scheme
        event_headers["X-Forwarded-Port"] = str(port)

        # APIGW does not support duplicate query parameters. Flask gives query params as a list so
        # we need to convert only grab the first item unless many were given, were we grab the last to be consistent
        # with APIGW
        query_string_dict = LocalApigwService._query_string_params(flask_request)

        event = ApiGatewayLambdaEvent(http_method=method,
                                      body=request_data,
                                      resource=endpoint,
                                      request_context=context,
                                      query_string_params=query_string_dict,
                                      headers=event_headers,
                                      path_parameters=flask_request.view_args,
                                      path=flask_request.path,
                                      is_base_64_encoded=is_base_64)

        event_str = json.dumps(event.to_dict())
        LOG.debug("Constructed String representation of Event to invoke Lambda. Event: %s", event_str)
        return event_str