I suggest it more like and addition to the already existing Stamp Set "Expressões Brasileiras".

It means that, in Brazil, the impossible is possible.

This origin of this expression is from the Second World War, where Brazil was making deals with both sides of the war without making a real positioning. With this kind of attitude, the people in Brazil used to say that Brazil was going to participate in the war "when the snake smokes" (quando a cobra fumasse). Or, in another words: never.

But it changed when the Axis powers attacked Brazilian merchant navy ships and the Government from here decided that it was time to deal with this situation more seriously and support the Allies by sending soldiers to fight abroad. These soldiers went to fight with a uniform in which there was a logo of a snake smoking, because something that everyone thought impossible was really happening and, also, to express that this action would have significant consequences, probably for both sides.

Curiosity: the image of a snake smoking was in the logo of my school, so we never forget the history of one of the soldiers that died in one of this battles.

https://pt.wikipedia.org/wiki/A_cobra_vai_fumar#:~:text=O%20ditado%20surgiu%20durante%20o,o%20Brasil%20entrar%20na%20Guerra%22.