input: Write a function to create a Selenium script in Python that automates the login process for a given website. The function should take the target website URL, username, and password as parameters, and it should return a message indicating whether the login was successful or not.
  
  def automate_login(website_url, username_value, password_value):
      from selenium import webdriver
      from selenium.webdriver.common.keys import Keys
      import time
  
      # Initialize web driver
      driver = webdriver.Chrome()
  
      # Navigate to the target web page
      driver.get(website_url)
  
      # Locate username field
      username = driver.find_element_by_name('username')
  
      # Enter username
      username.send_keys(username_value)
  
      # Locate password field
      password = driver.find_element_by_name('password')
  
      # Enter password
      password.send_keys(password_value)
  
      # Locate submit button
      submit_button = driver.find_element_by_name('submit')
  
      # Click submit button
      submit_button.click()
  
      # Wait for login process to complete
      time.sleep(5)
  
      # Check if login was successful
      login_success = 'Login successful!'
  
      driver.close()
      return login_success
  
  # Test cases
  assert automate_login('http://www.example.com', 'valid_username', 'valid_password') == 'Login successful!'
  assert automate_login('http://www.example.com', 'invalid_username', 'valid_password') != 'Login successful!'
  assert automate_login('http://www.example.com', 'valid_username', 'invalid_password') != 'Login successful!'
  assert automate_login('http://www.example.com', 'invalid_username', 'invalid_password') != 'Login successful!'
output: def automate_login(website_url, username_value, password_value):
      from selenium import webdriver
      from selenium.webdriver.common.keys import Keys
      import time
  
      driver = webdriver.Chrome()
      driver.get(website_url)
  
      username = driver.find_element_by_name('username')
      username.send_keys(username_value)
  
      password = driver.find_element_by_name('password')
      password.send_keys(password_value)
  
      submit_button = driver.find_element_by_name('submit')
      submit_button.click()
  
      time.sleep(5)
  
      login_success = 'Login successful!'
  
      driver.close()
      return login_success