phrase/ʒə t‿ɑ̃ pʁi/
I beg you, please; go ahead, please, help yourself (response to being asked permission, e.g. to come in, to pass someone, to start eating); you're welcome, don't mention it (familiar, in response to a thank you)
Synonyms: de rien, il n'y a pas de quoi, c'est moi