Non-quoted UTF-8 isn't parsed correctly

The .env:

UTF8=été
UTF8_QUOTED="été"

Python code:

import os
import dotenv

dotenv.load_dotenv()

print(list(os.environ.get('UTF8')))
print(list(os.environ.get('UTF8_QUOTED')))

Output:

> python foo.py 
['\\', 'x', 'e', '9', 't', '\\', 'x', 'e', '9']
['é', 't', 'é']

Expected output:

> python foo.py 
['é', 't', 'é']
['é', 't', 'é']