The problem is that the filename is updated everytime. At each step, you should make sure that the filename is only a filename. Something like this:
import os
if self.image:
self.image = compress(self.image)
self.image.name = os.path.basename(self.image.name)
I don’t know exactly what is your compress function, but maybe you could also check that it doesn’t do something weird with the filename.
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