How do I best adjust a timestamp with a timezone in python?
Question: I need to operate on dates within my pandas dataframe but my code has a bug.
Specifically I am importing a column of timestamps from a csv file.

    
    
    x['Created at']
    0       2016-05-13 13:28:41 -0400
    1       2016-05-13 05:11:18 -0400
    3       2016-05-12 18:06:42 -0400
    4       2016-05-12 16:06:24 -0400
    5       2016-05-12 13:58:01 -0400
    6       2016-05-12 03:30:27 -0400
    

I am then changing this data into a datetime. I am doing this via
`pandas.to_datetime(df['date'])` but when I do this, the time is getting
shifted by 4 hours.

    
    
    x.Createdat
    0      2016-05-13 17:28:41
    1      2016-05-13 09:11:18
    3      2016-05-12 22:06:42
    4      2016-05-12 20:06:24
    5      2016-05-12 17:58:01
    6      2016-05-12 07:30:27
    

I am assuming this is because of the `-0400` at the end of the timestamp but I
can not figure out the best way to resolve this issue so I can aggregate this
data in my own timezone.


Answer: If the -400 is information that you do not need or want, then simply change
your use of `pandas.to_datetime(df['date'])` to
`pandas.to_datetime(df['date'].apply(lambda x: x[:-6])` which will drop the
-400 from the string. Not the best and most robust approach, but it will work.

If you want to use the -400 but you want to convert it to a different
timezone, check out `tz_localize` as described in this answer: [convert gmt to
local timezone in pandas](http://stackoverflow.com/questions/34584500/convert-
gmt-to-local-timezone-in-pandas)

Another tool that should help is using `pytz`: [pytz - Converting UTC and
timezone to local time](http://stackoverflow.com/questions/25264811/pytz-
converting-utc-and-timezone-to-local-time)

