How to make auto-increment number

hello ,
in the " Chart of Accounts " there is a field called shown_number which is a number shown next to the account name in green label , i want to make this number unique + auto-increment based on the tree branches for example :

01-account
011-acount1
012-account2
013-account3

02-account
021 two
022 two
023 two

Hello,

This feature is not available for now. Can you please create Github Issue for it?