On Jun 8, 2010, at 7:38 PM, Fredrik Bonander wrote: > Real nice, thanks! Defiantly a great improvement. > > 2 questions. > > 1. Could you elaborate what these lines does? > > labelItems = db.get([Label.item.get_value_for_datastore(label) for label in > labelsData ])
db.get() can accept a list of keys to fetch; if it does, it returns a list of entities matching those keys. The parameter to db.get() is a list comprehension; it creates a list of keys of the item from each label. This allows you to get a list of keys of all the items of all the labels you fetched. > for label,labelItem in zip(labelsData,labelItems): zip(l1, l2) creates a list of tuples. Each element of the list is a tuple, with the first element of the tuple being an element in the first list, and the second element being the corresponding element in the second list. See http://docs.python.org/library/functions.html . The for loop unpacks through the list of tuples, matching labels to the fetched item for that label. Jan Michael Ibanez [email protected] -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
