Unable to get access token

Getting error bad request Client id not received with the request.
i am trying to get the access token like this
url = “https://api.codechef.com/oauth/token?grant_type=authorization_code&code="+code+“client_id=”+client_id+"&client_secret="+client_secret+"&redirect_uri=http://127.0.0.1:8000/oauth
headers = {
‘content-Type’: ‘application/json’
}
r = requests.post(url,headers = headers)

Please refer this documentation: https://developers.codechef.com/#steps-to-implement-oauth2-in-your-application

And for token request you should set post parameters.