Getting All Items from QListWidget and QTreeWidget in PyQt4

PyQt4 does not ship with helper methods for enumerating every item in QListWidget or QTreeWidget. Here are two straightforward patterns I found online:

QListWidget:

for i in range(0, listwidget.count()):
	item = listwidget.item(i)

QTreeWidget:

def tree_items(self, tree):
    it = QTreeWidgetItemIterator(tree)
    while it.value():
        yield it.value()
        it += 1

References:

1. 《How can I iterate through QListWidget items and work with each item?》
2. 《Using yield to iterate QTreeWidgetItem》