Inspired by ketem_studio clipper - but drawn from the scratch with bigger teeth and thicker body. There is no way that this clip will release your bag :)
I added two additional variants of the clip - if you have problems with opening clip after printing, try the weaker or weakest one (both have wider spacing between teeth)
I printed it with PLA, 0.3 mm layer. To make it a bit more flexible I set the vertical shells count to 2 and disabled the infill.
If you have problems with opening the clip just after printing, it may be caused by sticking together the opposite parts of the clip. Try to reduce a bit the amout of filament in slicer settings. When printing these clips sometimes I got 1st layer merged - it helped to increase the space between table and nozzle before printing.