Here is a list comprehension:
L = [{k: d[k](v) for (k, v) in l.iteritems()} for l in L]
where
L
is a list of or
Python dictionary unlike C++ dictionary are unordered because it uses hash for its keys. Analternative would be to use an ordered specialization of python dictionary called collections.OrdredDict.
This would turn your declaration as
from collections import OrderedDict
L = [OrderedDict((k, d[k](v)) for (k, v) in l.iteritems()) for l in L]