explicitly spelt out proof of equivariance avoids problem with automation due to type constructor `set`
explicitly spelt out proof of equivariance avoids problem with automation due to type constructor `set`

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle