Write `total_and_flatten(nested)` returning a tuple `(total, flat_list)` where `flat_list` is `nested` flattened one level using `itertools.chain`, and `total` is the sum via `functools.reduce`.
Required in your answer: chain(reduce(
Runs via Pyodide
from functools import reduce
from itertools import chain
def total_and_flatten(nested):
# TODO
pass
