def _table_union(left, right, distinct=False):
    op = _ops.Union(left, right, distinct=distinct)
    return TableExpr(op)
Called when the visible trait is changed on an action.
dataset/ETHPy150Open cloudera/ibis/ibis/expr/api.py/_table_union--crossover with--dataset/ETHPy150Open enthought/pyface/pyface/ui/qt4/action/action_item.py/_MenuItem._on_action_visible_changed