parameters: (cls, user_id, token)
return_statement: return None, None
docstring: Returns a user object based on a user ID and token.
  
          :param user_id:
              The user_id of the requesting user.
          :param token:
              The token string to be verified.
          :returns:
              A tuple ``(User, timestamp)``, with a user object and
              the token timestamp, or ``(None, None)`` if both were not found.
docstring_summary: Returns a user object based on a user ID and token.
docstring_tokens: Returns a user object based on a user ID and token .
function: def get_by_auth_token(cls, user_id, token):
          """Returns a user object based on a user ID and token.
  
          :param user_id:
              The user_id of the requesting user.
          :param token:
              The token string to be verified.
          :returns:
              A tuple ``(User, timestamp)``, with a user object and
              the token timestamp, or ``(None, None)`` if both were not found.
          """
          token_key = cls.token_model.get_key(user_id, 'auth', token)
          user_key = model.Key(cls, user_id)
          # Use get_multi() to save a RPC call.
          valid_token, user = model.get_multi([token_key, user_key])
          if valid_token and user:
              timestamp = int(time.mktime(valid_token.created.timetuple()))
              return user, timestamp
  
          return None, None
function_tokens: def get_by_auth_token ( cls , user_id , token ) : token_key = cls . token_model . get_key ( user_id , 'auth' , token ) user_key = model . Key ( cls , user_id ) # Use get_multi() to save a RPC call. valid_token , user = model . get_multi ( [ token_key , user_key ] ) if valid_token and user : timestamp = int ( time . mktime ( valid_token . created . timetuple ( ) ) ) return user , timestamp return None , None