[Tkinter-discuss] Filling a series of tk.Label

[Michael O'Donnell]

>From the Python Documentation on using * with a list:

Note also that the copies are shallow; nested structures are not
copied. This often haunts new Python programmers; consider:

>>> lists = [[]] * 3
>>> lists
[[], [], []]
>>> lists[0].append(3)
>>> lists
[[3], [3], [3]]

What has happened is that [[]] is a one-element list containing an
empty list, so all three elements of [[]] * 3 are (pointers to) this
single empty list. Modifying any of the elements of lists modifies
this single list. You can create a list of different lists this way:


>>> lists = [[] for i in range(3)]
>>> lists[0].append(3)
>>> lists[1].append(5)
>>> lists[2].append(7)
>>> lists
[[3], [5], [7]]