attribute 'tzinfo' of 'datetime.datetime' objects is not writable
How do I set the timezone of a datetime instance that just came out of the datastore?
When it first comes out it is in UTC. I want to change it to EST.
I'm trying, for example:
class Book( db.Model ):
creationTime = db.DateTimeProperty()
When a Book is retrieved, I want to set its tzinfo immediately:
book.creationTime.tzinfo = EST
Where I use this example for my EST object
However I get:
attribute 'tzinfo' of 'datetime.datetime' objects is not writable
I've seen a number of answers that recommend pytz and python-dateutil, but I really want an answer to this question.
Answer
datetime's objects are immutable, so you never change any of their attributes -- you make a new object with some attributes the same, and some different, and assign it to whatever you need to assign it to.
I.e., in your case, instead of
book.creationTime.tzinfo = EST
you have to code
book.creationTime = book.creationTime.replace(tzinfo=EST)