How can i put some information from a device to another device based on a parity condition?

Question

I have to solve a problem at work in pandas where i have a .csv file where i have some information like this:

Element --- Ticket
1-X1211 --- TT0045
1-X1212

I have 2 elements that form a pair based on 2 conditions:

1. The first 6 characters have to be the same for both of the elements in the pair.
2. The last number forms a pair like this 1 with 2, 3 with 4, 5&6, 7&8, 9&0. In this case you can see the pair: 1-X1211 pair with 1-X1212.

What i need to do is to associate the ticket from an element of the pair to the other element in the pair (if a ticket exists in the first place). So in this case to copy the ticket from 1-X1211 -> TT0045 and put it on the other element of the pair 1-X1212. Final it should look like this:

Element

1-X1211 --- TT0045

1-X1212 --- TT0045

I can't share a code because i don't know how to do it.

Thank you, Iulia