parameters: (self, flag_names, checker, message)
docstring: Constructor.
  
      Args:
        flag_names: [string], containing names of the flags used by checker.
        checker: function to verify the validator.
          input  - dictionary, with keys() being flag_names, and value for each
            key being the value of the corresponding flag (string, boolean, etc).
          output - Boolean. Must return True if validator constraint is satisfied.
            If constraint is not satisfied, it should either return False or
            raise Error.
        message: string, error message to be shown to the user if validator's
          condition is not satisfied
docstring_summary: Constructor.
docstring_tokens: Constructor .
function: def __init__(self, flag_names, checker, message):
      """Constructor.
  
      Args:
        flag_names: [string], containing names of the flags used by checker.
        checker: function to verify the validator.
          input  - dictionary, with keys() being flag_names, and value for each
            key being the value of the corresponding flag (string, boolean, etc).
          output - Boolean. Must return True if validator constraint is satisfied.
            If constraint is not satisfied, it should either return False or
            raise Error.
        message: string, error message to be shown to the user if validator's
          condition is not satisfied
      """
      super(DictionaryValidator, self).__init__(checker, message)
      self.flag_names = flag_names
function_tokens: def __init__ ( self , flag_names , checker , message ) : super ( DictionaryValidator , self ) . __init__ ( checker , message ) self . flag_names = flag_names