Spooled Wrapper Fail

spooled_wrapper_fail.py

from csv import DictReader, DictWriter
from io import TextIOWrapper
from tempfile import SpooledTemporaryFile

csv_lines = ["A;2;3", "B;4;6", "C;8;12"]
fieldnames = ["Foo", "Bar", "Baz"]
csv_reader = DictReader(csv_lines, fieldnames=fieldnames, delimiter=";")
with SpooledTemporaryFile(mode="w+b") as tmp:
    with TextIOWrapper(tmp, encoding='utf-8') as wrapper:
        writer = DictWriter(wrapper, fieldnames=fieldnames)
        for row in csv_reader:
            writer.writerow({"Foo": row["Foo"], "Bar": row["Bar"], "Baz": row["Baz"]})

    tmp.seek(0)