Pythonic way to check if two dictionaries have the identical set of keys?

Question

For example, let's say I have to dictionaries:

d_1 = {'peter': 1, 'adam': 2, 'david': 3}

and

d_2 = {'peter': 14, 'adam': 44, 'david': 33, 'alan': 21}

What's the cleverest way to check whether the two dictionaries contain the same set of keys? In the example above it should return False because d_2 contains the 'alan' key, which d_1 doesn't. Please note that I am not interested in checking that the associated values for each and every key are the same, just that the set of keys are the same.

Answer 1

>>> not set(d_1).symmetric_difference(d_2)
False
>>> not set(d_1).symmetric_difference(dict.fromkeys(d_1))
True

Answer 2

A quick option (not sure if its the most optimal)

len(set(d_1.keys()).difference(d_2.keys())) == 0

Answer 3

In Python2,

set(d_1) == set(d_2)

In Python3, you can do this which may be a tiny bit more efficient than creating sets

d1.keys() == d2.keys()

although the Python2 way would work too

Answer 4

One way is to check for symmetric difference (new set with elements in either s or t but not both):

set(d_1.keys()).symmetric_difference(set(d_2.keys()))

But a shorter way it to just compare the sets:

set(d_1) == set(d_2)

Answer 5

You can get the keys for a dictionary with dict.keys().

You can turn this into a set with set(dict.keys())

You can compare sets with ==

To sum up:

set(d_1.keys()) == set(d_2.keys())

will give you what you want.