It became a jazz standard, but Benny Goodman thought he would show up young Charlie Christian, the electric guitarist who had not done well in the tryout earlier that day, by calling for that song when Christian was inexplicably inserted onstage by friends that night in 1939.
Charlie obliged by doing 40 different improvisations as the verse came to him 40 times, bringing down the house. Goodman - the pioneer in integrating his bands - was sold and signed him on. I'm not knowledgeable about jazz, but notice the two verses improvised in the middle of this recorded piece: same music, very different.
Also notice. Charlie Christian's early style was guitar work attempting to sound like horns, only later putting the imprint on the instrument as a solo item. This sounds about halfway in-between here. Does anyone know?