cred_values = {'username': 'myuser', 'password': 'mypwd'}

username = cred_values['username']

password = cred_values['password']

login_data = {'username': username,'password': password}

login_response = requests.post(login_request_url, headers=login_headers, data=login_data)

login_data = {'username': '' + username + '','password': '' + password + ''}

login_data = {'username': '' + str(username) + '','password': '' + str(password) + ''}

login_response = requests.post(login_request_url, headers=login_headers, data=json.dumps(login_data))