Passing args, kwargs, to run_in_executor

Use functools.partial; it’s a standard way to do such things, and it’s specifically recommended in the docs for loop.run_in_executor, as well as more generally in the Event Loop docs.

Here’s how it might look for you:

import functools  # at the top with the other imports

loop.run_in_executor(None, functools.partial(update_contacts, data={
    'email': email,
    'access_token': g.tokens['access_token']
}))

You could also do from functools import partial, if you like.