Hanna-Barbera, 1956-71.
These outrageous magpies were the stars of Terrytoons
galaxy of cartoon line-up of Saturday Morning and Sunday Morning
shows which featured also in the category Mighty Mouse,Deputy
Dawg and many more, and it was sponsored by General Mills cereals.
As for the birds themselves, you had a smart alec New York bird,
and a proper speaking British one who were always getting into
all sorts of trouble and for one it was hilariously funny especially
with the birds getting into mischief.