You'll be given a list of two strings, and each will contain exactly one colon (`":"`) in the middle (but not at beginning or end). The length of the strings, before and after the colon, are random.
Your job is to return a list of two strings (in the same order as the original list), but with the characters after each colon swapped.
## Examples
```
["abc:123", "cde:456"]  -->  ["abc:456", "cde:123"]
["a:12345", "777:xyz"]  -->  ["a:xyz", "777:12345"]
```
def tail_swap(lst):
    (a,b),(c,d) = (s.split(':') for s in lst)
    return list(map(':'.join, ((a,d),(c,b))))
def tail_swap(lst):
    (a,b),(c,d) = (s.split(':') for s in lst)
    return list(map(':'.join, ((a,d),(c,b))))