What is the right format for label for multi label in fasttext?

Question

Currently I am working on Stack overflow tag prediction where I am using fasttext for text classification.

I wanted to know that what is the correct format for label for

Answer 1

The third is the correct format, as you can see in this example file from FastText tutorial for text classification:

__label__sauce __label__cheese How much does potato starch affect a cheese sauce recipe? __label__sauce __label__storage-lifetime __label__acidity __label__mayonnaise Regulation and balancing of readymade packed mayonnaise and other sauces