如何下载一个文件名。点前缀?

谢谢

@app.route('/.blah.auth', methods=['GET'])
def downloadBlahAuth(roleLevel = app.config["PAGE_ROLE_LEVELS"][".blah.auth"]):
  """
  filePath = os.path.join(app.config["DOWNLOADS_FOLDER"], ".blah.auth");
  theFile = open(filePath, "r")
  fileText = theFile.read()
  theFile.close()

  strIO = StringIO.StringIO()
  strIO.write(fileText)
  strIO.seek(0)
  return send_file(strIO, attachment_filename=".blah.auth", as_attachment=True)
  """
  fileName = ".blah.auth"
  return send_from_directory(directory=app.config["DOWNLOADS_FOLDER"], filename=fileName)