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Is it possible to have a dictionary or set comprehension inside of an f-string in python 3.6+?

It seems syntactically impossible:

names = ['a', 'b', 'c']
pks = [1, 2, 3]

f"{{name : pk for name, pk in zip(names, pks)}}"

This will return:

{name : pk for name, pk in zip(names, pks)}

This is expected behavior, double brackets result in literal brackets in the output as the expression isn't evaluated.

Has anyone found a workaround to allow for dictionary/set comprehensions inside of f-strings?

Connor Rice
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1 Answers1

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Add spaces, they are syntactically required and won’t appear in the resulting string:

names = ['a', 'b', 'c']
pks = [1, 2, 3]
f"{ {name: pk for name, pk in zip(names, pks)} }"
#  ▲                                          ▲
#  │                                          │ 
#  ╰───────────────See the spaces?────────────╯ 
Lars Blumberg
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