<prompt> Translate the following text to SwahiliThe heir to what was once the worlds largest private oil fortune received his British passport in the week before Christmas and immediately revoked his US nationality, the newspaper said.  <response>: Mrithi wa mali kubwa zaidi ya mafuta duniani, ambaye alikuwa na utajiri mkubwa wa mafuta, alipokea pasipoti yake ya Uingereza wiki moja kabla ya Krismasi na mara moja akaondoa uraia wake wa Marekani. 