Use literal dict instead of calling dict() in Airflow core

[hussein-awala]

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[potiuk]

Hmmm. Not so sure about this one . I actually like better the dict variant. What's the reason you want to change it @hussein-awala ? (Not strongly opposing - but wanted to know the reasoning).

[Lee-W]

Hmmm. Not so sure about this one . I actually like better the dict variant. What's the reason you want to change it @hussein-awala ? (Not strongly opposing - but wanted to know the reasoning).

AFAIK, {} seems to perform a bit (not noticeable) better than dict(). I like literal dict a bit better (more readable to me). Especially in a place like here.

[potiuk]

Yeah. Performance is noticeably faster. Fine for me

From https://stackoverflow.com/questions/6610606/is-there-a-difference-between-using-a-dict-literal-and-a-dict-constructor

Literal is much faster, since it uses optimized BUILD_MAP and STORE_MAP opcodes rather than generic CALL_FUNCTION:

python2.7 -m timeit "d = dict(a=1, b=2, c=3, d=4, e=5)"
1000000 loops, best of 3: 0.958 usec per loop

python2.7 -m timeit "d = {'a':1, 'b':2, 'c':3, 'd':4, 'e':5}"
1000000 loops, best of 3: 0.479 usec per loop

python3.2 -m timeit "d = dict(a=1, b=2, c=3, d=4, e=5)"
1000000 loops, best of 3: 0.975 usec per loop

python3.2 -m timeit "d = {'a':1, 'b':2, 'c':3, 'd':4, 'e':5}"
1000000 loops, best of 3: 0.409 usec per loop