Slicing a Python OrderedDict

Question

In my code I frequently need to take a subset range of keys+values from a Python OrderedDict (from collections package). Slicing doesn\'t work (throws Typ

Answer 1

I wanted to slice using a key, since I didn't know the index in advance:

o = OrderedDict(zip(list('abcdefghijklmnopqrstuvwxyz'),range(1,27)))

stop = o.keys().index('e')           # -> 4
OrderedDict(islice(o.items(),stop))  # -> OrderedDict([('a', 1), ('b', 2), ('c', 3)])

or to slice from start to stop:

start = o.keys().index('c')                    # -> 2
stop = o.keys().index('e')                     # -> 4
OrderedDict(islice(o.iteritems(),start,stop))  # -> OrderedDict([('c', 3), ('d', 4)])