input: Write a function to implement a web scraper using Python's Selenium that retrieves data from an online store, prints the names of the products after entering a search keyword, and closes the browser window.
  assert web_scraper()==None
  assert web_scraper()==None
  assert web_scraper()==None
  assert web_scraper()==None
  assert web_scraper()==None
output: def web_scraper():
      from selenium import webdriver
      from selenium.webdriver.common.by import By
      from selenium.webdriver.common.keys import Keys
  
      driver = webdriver.Chrome()
      driver.get("https://www.example-online-store.com")
      
      search_box = driver.find_element(By.NAME, "q")
      search_box.send_keys("search keyword")
      search_box.send_keys(Keys.RETURN)
      
      products = driver.find_elements(By.CLASS_NAME, "product-name")
      for product in products:
          print(product.text)
      
      driver.quit()