Supporting Timezones in Google App Engine

One of the features in the latest iteration of My Web Brain is timezone support. Google App Engine does not provide ideal support for timezones. DateTimeProperty objects with timezone information are converted by the datastore into UTC. When datetime objects are retrieved, no timezone information is present.

Many people using python with Google App Engine are old python hands. Some have experience with implementing timezone support.  I am neither, so after some research I and experimentation I thought I would write about how I managed to build timezone support into my application. Apologies for any  serious errors - I hope someone corrects me.

Note: All of my examples are taken from a machine running Windows 7.

I intend to cover the subject in a series of posts:

• Part 0: The Starting Point - What you get out the box from Google App Engine and the Base Python Environment. 
• Part 1: Getting Timezone information with pytz
• Part 2: Making the Google App Datastore more consistent by writing a UtcDatetimeProperty class
• Part 3: Handling timezones throughout your application

 Hopefully someone will find the discussion useful or even better contribute ways to achieve the same effect.