Is Parent Item Group not allowed in transaction?

In item group, it was mentioned as “Only leaf nodes are allowed in transaction”. did any one know, which transactions it was pointing to?

Please check this reference: Limit Group Item list to only Children Choices / How to query a Link Field - #3 by nabinhait

Hey, i am not asking this.

it was mentioned as “Only leaf nodes are allowed in transaction”. But, i didn’t see any restrictions for parent item group in ERPNext.

Which transactions?

that is what i am asking