Published: 25 March 2021, 18:00
PEP-589 (landed in Python 3.8) introduced typing.TypedDict
as a way to annotate dicts:
from typing import TypedDict
class Movie(TypedDict):
name: str
year: int
movie: Movie = {
'name': 'Blade Runner',
'year': 1982,
}
It cannot have keys that aren’t explicitly specified in the type:
movie: Movie = {
'name': 'Blade Runner',
'year': 1982,
'director': 'Ridley Scott', # fails type checking
}
Also, all specified keys are required by default but it can be changed by passing total=False
:
movie: Movie = {} # fails type checking
class Movie2(TypedDict, total=False):
name: str
year: int
movie2: Movie2 = {} # ok