Transactionnal decorator for Python & GCP Datastore

main.py

from google.cloud import datastore
from .transactionnal import transactionnal

client = datastore.Client('<project-id>', '<namespace>')

key = <get a key somehow>

##
# > @transactionnal(client)
# > def _():
# is equivalent to
# > with client.transaction():
# but it cannot fail
@transactionnal(client)
def _():
   player = client.get(key)
   player['total_points'] += 10
   client.put(player)

transactionnal.py

from tenacity import retry, retry_if_exception_type, wait_random, stop_after_attempt
from google.api_core import exceptions

##
# Simple decorator to be able to reproduce the behaviour of the `with`
# keyword for transactions
def transactionnal(client, *args, **kwargs):
    if callable(client):
        raise TypeError('transactionnal() missing 1 required positional argument: \'client\'')
    @retry(
        retry=retry_if_exception_type(exceptions.Aborted),
        wait=wait_random(.1, .3),
        stop=stop_after_attempt(7))
    def _(f):
        with client.transaction():
            f(*args, **kwargs)
    return _

Reserved