def marks(value):
        """list or KeyedList of ``Mark`` : Mark definitions

        Marks are the visual objects (such as lines, bars, etc.) that
        represent the data in the visualization space. See the :class:`Mark`
        class for details.
        """
        for i, entry in enumerate(value):
            _assert_is_type('marks[{0}]'.format(i), entry, Mark)
def marks ( value ) : for i , entry in enumerate ( value ) : _assert_is_type ( 'marks[{0}]' . format ( i ) , entry , Mark )
list or KeyedList of ``Mark`` : Mark definitions

        Marks are the visual objects (such as lines, bars, etc.) that
        represent the data in the visualization space. See the :class:`Mark`
        class for details.