I have some time data that I need to convert to a proper datetime with

```
data['dep_time'] = pd.to_datetime(data['dep_time'], format='%H:%M').dt.time

```

The problem is in each cell I have an inconsistent number of digits

I might have '1714' or '714' or just '6'.

I want to use format to change each str to the format 00:00, but I have to start from the back of the str and assume that if I just have '6' it means '00:06'

```
        year  month  day  dep_time  dep_delay  arr_time  arr_delay  cancelled  \
103992  2014      5   11      1013         -2      1247        -13          0   
103993  2014      5   11      1929         -1      2215        -24          0   
103994  2014      5   11      1117          5      1355          9          0   
103995  2014      5   11       736        -10       924        -18          0   
103996  2014      5   11      1340          0      1647         10          0   

```