Passing an explicit tuple to format string.
Passing an explicit tuple to format string.

This way, if the **actual** value is a tuple, formatting
will still work without a `TypeError`.

// edited by skirpichev

Signed-off-by: Sergey B Kirpichev <6c6368f8f4cbabf33ffd2abfd270a2fcf839188a@gmail.com>

skirpichev/omg,diofant/diofant