id,summary,reporter,owner,description,type,status,component,version,severity,resolution,keywords,cc,stage,has_patch,needs_docs,needs_tests,needs_better_patch,easy,ui_ux 21290,"Add migration docs for (or avoid) ""Cannot serialize"" errors",Tim Graham,Andrew Godwin,"The migration writer raises a `ValueError: Cannot serialize: ` for models that have defaults like: 1. `models.DateField(default=datetime.today)` 2. `models.DecimalField(default=Decimal('1.000')` Suggested workarounds by loic84 in IRC: 1. `datetime.date.today` is whitelisted, `datetime.datetime.today` isn't. 2. `def default_decimal(): return Decimal('1.000')` then `default=default_decimal.` This is confusing for users coming from south where things just worked. We should either add docs about this problem or figure out a way to avoid these errors.",Cleanup/optimization,closed,Migrations,dev,Release blocker,fixed,,loic@…,Accepted,0,0,0,0,0,0