Quoted from Sacramento Bee:

Yakov Smirnoff on his communication with friends who came to America before him:

Before they left, we worked out a code that they would say the opposite of
what they meant in their letters, Smirnoff recalled. When they wrote that
the streets are filthy and the people are rude, we thought that they meant
the people were friendly and the streets were clean. Since they live in
Cleveland, we later learned they had forgotten the code.