code: def check_csrf_token():
      
      if request.method in ("GET",): # not exhaustive list
          return
      token = request.form.get("csrf_token")
      if token is None:
          app.logger.warning("Expected CSRF Token: not present")
          abort(400)
      if not safe_str_cmp(token, csrf_token()):
          app.logger.warning("CSRF Token incorrect")
          abort(400)
docs: Checks that token is correct, aborting if not