I have two dataframe like this
```
v1. v2
1 a,b,c 1,2,3
2 d,e,f,g 4,6
3 h,k,v,x 9,0
```
```
v1 v2
1 a AA
2 c CC
3 d DD
```
after combine
```
v1 v2 v3
1 a,b,c 1,2,3 AA,CC
2. d,e,f,g 4,6 DD
3 h,k,v,x 9,0
```
I dont know how to perform like this , any comment would be appreciated