code: def Add(self, key, help="", default=None, validator=None, converter=None, **kw):
          
  
          if SCons.Util.is_List(key) or isinstance(key, tuple):
              self._do_add(*key)
              return
  
          if not SCons.Util.is_String(key) or \
              not SCons.Environment.is_valid_construction_var(key):
                  raise SCons.Errors.UserError("Illegal Variables.Add() key `%s'" % str(key))
  
          self._do_add(key, help, default, validator, converter)
docs: Add an option.
  
  
          @param key: the name of the variable, or a list or tuple of arguments
          @param help: optional help text for the options
          @param default: optional default value
          @param validator: optional function that is called to validate the option's value
          @type validator: Called with (key, value, environment)
          @param converter: optional function that is called to convert the option's value before putting it in the environment.