Posting to save someone time.

Python3 / Selenium / Firefox Webdriver

from selenium import webdriver
from selenium.webdriver.common.keys import Keys
import time
browser = webdriver.Firefox()
browser.get("https://<INSTANCE URL>/side_door.do") 
time.sleep(10)

browser.switch_to.frame("gsft_main")
username = browser.find_element_by_id("user_name")
password = browser.find_element_by_id("user_password")
username.send_keys("<USER ACCOUNT>")
password.send_keys("<USER ACCOUNT PASSWORD")
login_attempt = browser.find_element_by_id("sysverb_login")
login_attempt.click()