Checklist

• I have verified that that issue exists against the master branch of Django REST framework.
• I have searched for similar issues in both open and closed tickets and cannot find a duplicate.
• This is not a usage question. (Those should be directed to the discussion group instead.)
• This cannot be dealt with as a third party library. (We prefer new functionality to be in the form of third party libraries where possible.)
• I have reduced the issue to the simplest possible case.
• I have included a failing test as a pull request. (If you are unable to do so we can still accept the issue.)

Steps to reproduce

1. Intall pytz (along with Django and django-rest-framwork);
2. Set settings.TIME_ZONE = 'America/New_York';
3. Make a serializor with DateTimeField;
4. Try to serialize '2017-03-12T02:30:00'.

or

2. Execute DateTimeField(default_timezone=pytz.timezone('America/New_York')).to_internal_value('2017-03-12T02:30:00')

Expected behavior

ValidationError raised with appropriate message.

Actual behavior

NonExistentTimeError/AmbiguousTimeError propagated from pytz.