how do you specify the type of an

OrderedDict

in python3.6? https://docs.python.org/3.7/library/typing.html#typing.OrderedDict was only added in 3.7

There’s no need for OrderedDict. Dictionaries are already insertion ordered

they still are slightly different, so you can use

typing.MutableMapping

to put in types for `OrderedDict`s if you need it