Python: Define every item in List as set

What I have:

I have this List:

[in]:  a=['Hamburg','Berlin','Teheran','Chicago']
[out]: ['Hamburg', 'Berlin', 'Teheran', 'Chigaco']

What i did:

I convert this list to set

[in]: set_a=set(a)
[out]: {'Chigaco', 'Berlin', 'Hamburg', 'Teheran'}

What I want:

[{'Chigaco'}, {'Berlin'}, {'Hamburg'}, {'Teheran'}]

Answer

Brackets needed in b :

a=['Hamburg','Berlin','Teheran','Chicago']
b=[set([el]) for el in a]