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- Biden described himself as the "first black woman" in an interview with Wurd radio station.
- It comes just days after Biden's disastrous debate with former US president Donald Trump.
- Biden said he needs to get more sleep and stop holding events after 8 p.m., according to reports.
Joe Biden's argument that his disastrous debate performance last week was a one-off is seemingly falling apart.
In his latest verbal slip-up, the president seemingly said he is "proud" to be the first "black woman to serve with a black president."