FirstNature hummingbird feeder wasp/yellow jacket/bee/ant deterrent

After trying to trap the yellow jackets and only getting a few dozen it was obvious that traps would not do the trick so I tried printing some wasp/yellow jacket/ bee proof feeders. They all leak 5 of them. Now the yellow jackets are swarming all over the last one still hanging so they are obviously getting fed by it.

Time for the next step. Make the feeders we already have only let the hummingbirds get the food. After reading a bit I came up with the simple solution of making a grommet for t