Where can I put the Branch ID?

edit

What can I do to Off/On a specific branch " in Service ", If the From Bus Number and To Bus Number are the same?

Where can I put the Branch ID?

There are two buses and two branches, as shown in the picture below.

Branch_1：From 123 To 456 ，Branch ID：A

Branch_2：From 123 to 456，Branch ID：B

https://ibb.co/T8VPZDS

psspy.branch_chng(123,456,r"""1""",[0, _i, _i, _i, _i, _i], [f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f])

psspy.branchchng(123,456,r"""1""",[1, _i, _i, _i, _i, _i], [f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f, _f])

Thank you for reading my question!