old_contents: import aiohttp.web
  import re
  
  
  async def check_hex_color(req: aiohttp.web.Request):
      """
      Return error text if the Hex color in the request is not valid.
  
      """
      regex = "^#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})$"
  
      match = re.match(regex, req["data"]["color"])
  
      return match
  
new_contents: import aiohttp.web
  import re
  
  
  async def check_hex_color(req: aiohttp.web.Request):
      """
      Check if the Hex color in the request is valid.
  
      """
      regex = "^#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})$"
  
      match = re.match(regex, req["data"]["color"])
  
      return match
  
subject: Update the Docstring in checks.py