docs: def get_session_user(session_id, **kwargs):
      """
          Given a session ID, get the user ID that it is associated with
  
          args:
              session_id (string): The user's ID to identify the cookie to remove
  
          returns:
              user_id (string) or None if the session does not exist
      """
  
      hydra_session_object = session.SessionObject({}, #This is normally a request object, but in this case is empty
              validate_key=config.get('COOKIES', 'VALIDATE_KEY', 'YxaDbzUUSo08b+'),
              type='file',
              cookie_expires=True,
              data_dir=config.get('COOKIES', 'DATA_DIR', '/tmp'),
              file_dir=config.get('COOKIES', 'FILE_DIR', '/tmp/auth'))
  
      hydra_session = hydra_session_object.get_by_id(session_id)
  
      if hydra_session is not None:
          return hydra_session['user_id']
  
      return None