[NTG-context] Alternating left and right margins

Hello How to setup the layout where each even page has right and left margins swapped (for booklet-like printing) E.g. if I have 1 cm right margin and 2cm left, second, forth and so on pages should have 2 cm right margin and 1cm left. My current layout is \setuppapersize [A5][A5] \setuplayout[topspace=1.5cm, header=0cm, footer=0.7cm, bottomspace=0.7cm, height=fit, leftmargin=1.5cm, rightmargin=1.5cm, backspace=1.5cm, width=fit] \showframe Best, Vyatcheslav