Explainer-What is at stake for investors in Angola's elections?

FILE PHOTO: The Estadio da Cidadela stadium is seen with the skyline of central Luanda May 4, 2014. REUTERS/Saul Loeb/File Photo

LONDON/LUANDA (Reuters) - Angolan voters will choose next Wednesday between a party that's been in power for nearly five decades and its main opponent for even longer, in what looks like the closest ever election in Africa's second-biggest oil producer.

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