本周第一天：

DATEDELTA(dateInWeek(TODAY(),1),-2)

本周最后一天：

DATEDELTA(dateInWeek(TODAY(),-1),-2)

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测试了下，这个需要判断后做设置

第一天：

if(OR(WEEKDAY($日期)=0,WEEKDAY($日期)=6),DATEDELTA(dateInWeek(DATEDELTA($日期,2),1),-2),DATEDELTA(dateInWeek($日期,1),-2))

最后一天

if(OR(WEEKDAY($日期)=0,WEEKDAY($日期)=6),DATEDELTA(dateInWeek(DATEDELTA($日期,2),-1),-2),DATEDELTA(dateInWeek($日期,-1),-2))

DATEDELTA(dATEINWEEK("2023-04-01",-1),-1)//周六

DATEDELTA(dATEINWEEK("2023-04-01",-1),-1)+6//周五