Discovered this while trying to use a function in `boto3`. Seems like when tzlocal() is passed with a 0 to datetime.datetime.fromtimestamp(), it throws an "[Errno 22] Invalid argument" error. Using 3.7.4 via Anaconda on Windows 10, and tzlocal().tznames's local timezone for me is EST/EDT.

Can replicate through this:
```
import datetime
from dateutil.tz import tzlocal

print(datetime.datetime.fromtimestamp(0, tzlocal()))
```