input: Write a function to crawl a website for a specific type of data and return the data found. The function should take a website URL as input and search for phone numbers in the format `###-###-####`. If no phone numbers are found, it should return an empty list.
  assert crawl_website_for_phone_numbers('www.example.com')==['123-456-7890']
  assert crawl_website_for_phone_numbers('www.example.org')==[]
  assert crawl_website_for_phone_numbers('www.example.net')==['987-654-3210', '012-345-6789']
  assert crawl_website_for_phone_numbers('www.example.io')==[]
  assert crawl_website_for_phone_numbers('www.example.com')==['555-555-5555']
output: import re
  import requests
  
  def crawl_website_for_phone_numbers(url):
      response = requests.get(url)
      if response.status_code != 200:
          return []
      phone_numbers = re.findall(r'\d{3}-\d{3}-\d{4}', response.text)
      return phone_numbers