how to build paths and responses object for a url - swagger

Question

i would like to create the path object for the following url
url: "http://127.0.0.1:5000"
in the code when the user enters the above mentioned url followed by slash \ a method called start() is to be called and executed.
that method when called it receives response from the backend in form of json file and it retuens it.
how to build the path and responses object for such action please
code:
#app.route("/", methods=['GET','POST'] )
def startCoord2():
baseURL = "https://api.openrouteservice.org/v2/directions/driving-car?api_key=5b3ce3597851110001cf62480ecf8c403567479a87de01df5da651fb&start=8.681436,49.414554&end=8.681561,49.414747"
with urllib.request.urlopen(baseURL) as response:
print ("str(response): " + str(response))
print ("str(response.getCode(): " + str(response.getcode()))
data = response.read()
print ("response.read(): " + str(data))
dataAsJSONObject = json.loads(data)
distance = str(dataAsJSONObject["features"][0]['properties']['segments'][0]['distance'])
return dataAsJSONObject #config['EndPoint']['url'] + config['EndPoint']['api_key'] + "&start=" + startLat + "," + startLng + "&end=" + end1Lat + "," + endLng + ""
yaml file:
openapi: '3.0.2'
info:
title: &apiTitle "Distance micro-service API."
description: "This micro-service receives four comma separated GPS coordinates in the following order, startLongitude, startLatitude, endLongitude
, endLatitude in the url. Then it receives a response in a form of json file. The json file is to be fetched for the distance which represents the distance between
the aforementioned GPS coordinates"
version: '1.0'
termsOfService: "http://127.0.0.1:5000/getDistance/terms"
contact:
name: " "
url: "http://127.0.0.1:5000"
email: "me#provider.com"
license:
name: "CC Attribution-ShareAlike 4.0 (CC BY-SA 4.0)"
url: "https://openweathermap.org/price"
servers:
- url: http://127.0.0.1:5000
description: Local host test server. When accessed it will return the distance from Berlin to Alexandria in Egypt in kilometers.
variables:
originAndDestinationGPSCoords:
default: 13.404954,52.520008,29.924526,31.205753
description:
Local host test server. When accessed it will return the distance from Berlin to Alexandria in Egypt in kilometers.
paths:
/:
get:
tags:
- "get response data in json format"
summary:
get the distance between 8.681436,49.414554,8.681561,49.414747
description: >
to display data in json formate
responses:
'200':
description: Distance fetched successfully.