Thank you Anthony. That is very clear now.
On Apr 10, 7:27 am, Anthony <abasta...@gmail.com> wrote: > On Saturday, April 9, 2011 6:37:15 PM UTC-4, niknok wrote: > > > Hello. > > > What is the difference between the statements: import datetime vs from > > datetime import datetime > > > I got stuck with my IS_DATE_IN_RANGE error "<type > > 'exceptions.AttributeError'>(type object 'datetime.datetime' has no > > attribute 'timedelta')" until i added "import datetime" to the controller. > > All the while, I thought I already loaded datetime because I already have > > this line: "from datetime import datetime". > > The different methods of importing result in different namespaces -- > seehttp://effbot.org/zone/import-confusion.htm. > > The datetime module is probably particularly confusing because the module > also includes a datetime class, so datetime.datetime refers to the datetime > class within the datetime module. If you do 'from datetime import datetime', > you're only importing the datetime class, so when you refer to 'datetime' in > your code, it's referring to the datetime class, not the whole datetime > module. That means 'datetime.timedelta' won't work, because it's expecting > 'timedelta' to be an attribute of the datetime class, when it's actually a > class within the datetime module. If you want to use from-import to access > the timedelta class, you can do 'from datetime import timedelta', and then > you can refer to 'timedelta' directly. > > Anthony
