A vacuum cleaner with a handkerchief over a small tube held or taped to the vacuum hose in such a way as to not lose suction with the smaller tube. (or try it without the tube). The cloth is to make sure you catch the part instead of it being vacuumed up.
The more loose the weave is in the fabric, the more suction you will have.
Or, some SuperGlue (the tiniest amount) or five minute epoxy on the end of a toothpick which has the sharp end removed. Set the slightest amount of the glue onto the toothpick tip and stick it (literally) into the little hole to set up the glue between the toothpick and the detent part.