America's First Lady is joking about life in the White House.  During an event in Tanzania on empowering women, Michelle Obama was asked if living in the White House was like being in a prison.  She said "there are prison elements to it, but it's a really nice prison."  As laughter erupted, former First Lady Laura Bush pointed out that this particular prison has a chef.  The Obamas are wrapping up a three-nation African tour.  This was Barack Obama's first extended trip to the continent as President.