Replace == by is for types comparison

[hussein-awala]

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[uranusjr]

Not sure this is advantaguous. Readability is approximately on par, but

$ py -m timeit -s 't = dict; from typing import Dict' 't in (Dict, dict)'
10000000 loops, best of 5: 35.9 nsec per loop
$ py -m timeit -s 't = dict; from typing import Dict' 't in (dict, Dict)'
10000000 loops, best of 5: 25 nsec per loop

$ py -m timeit -s 't = dict; from typing import Dict' 't is Dict or t is dict'
20000000 loops, best of 5: 13.7 nsec per loop
$ py -m timeit -s 't = dict; from typing import Dict' 't is dict or t is Dict'
20000000 loops, best of 5: 9.98 nsec per loop

$ py -m timeit -s 't = dict; from typing import Dict' 't == Dict or t == dict'
10000000 loops, best of 5: 27.2 nsec per loop
$ py -m timeit -s 't = dict; from typing import Dict' 't == dict or t == Dict'
20000000 loops, best of 5: 13.8 nsec per loop

both the is and == versions are consistently faster. Considering we’re comparing types here, is would be best IMO.