def __init__(self, arg, arg_type, value):
super().__init__()<EOL>self.arg = arg<EOL>self.type = arg_type<EOL>self.value = value<EOL>
Save attributes.

        See the definition of the attributes on the class for more information about
        the arguments.

        Arguments
        ---------
        arg : string
        arg_type : string
        value : string, number, ``False``, ``True`` or ``None``