I want to summarize some scripts execution time. I try to do it via tcl.
As an input I have :

```
00:00:00:09
00:00:34:05
00:00:50:34
.....

```

Input format is `<days:hours:minutes:seconds>`

How can I summarize the time and get one output as summarized output.

Output format: `<days:hours:minutes:seconds>`