y56

from collections import OrderedDict
myOrderedDict = OrderedDict()
myOrderedDict['a'] = 1
myOrderedDict['b'] = 2
myOrderedDict.popitem(last = False)  # Setting last to False signals you wanted to remove the first. 

y56

https://stackoverflow.com/questions/6130768/return-none-if-dictionary-key-is-not-available

You can use dict.get()

value = d.get(key)

which will return None if key is not in d. You can also provide a different default value that will be returned instead of None:

value = d.get(key, "empty")

y56

https://stackoverflow.com/questions/664118/whats-the-difference-between-dict-and

>>> from timeit import timeit
>>> timeit("a = {'a': 1, 'b': 2}")
0.424...
>>> timeit("a = dict(a = 1, b = 2)")
0.889...