import requests

def auth(username, password, url):
    authurl = url + "/api/v1/auth/authenticate-user" 
    myobj = {'username': username, 'password':password} 
    data = requests.post(authurl, data = myobj) # this posts the username and password to the api
    #print(data.json())
    refreshToken = data.json()['refreshToken'] # this is the refresh token
    accessToken = data.json()['accessToken'] # this is the access token
    accessTokenExpiration = data.json()['accessTokenExpiration'] # this is the access token expiration date
    access_info = {'accessToken': accessToken, 'accessTokenExpiration': accessTokenExpiration, 'refreshToken': refreshToken} # this is the access token, refresh token and expiration info
    return access_info # returns the information

creds = auth("username","password","https://yourinstance.com";)