PEP257说:Docstringprocessingtoolswillstripauniformamountofindentationfromthesecondandfurtherlinesofthedocstring,equaltotheminimumindentationofallnon-blanklinesafterthefirstline.Anyindentationinthefirstlineofthedocstring(i.e.,uptothefirstnewline)isinsignificantandremoved.Relativeindentationoflater