Currently packages are unique by their filename, so there can't be custom versions of any package already present in Pulp. By changing the uniqueness constraint to the sha256 one user can have a package from PyPI in their repository and another user upload their own custom version of that package with no conflicts in Pulp. At the repo level, the package filename should still be the uniqueness constraint as the simple api doesn't allow for indexes to have packages of the same name.
Currently packages are unique by their filename, so there can't be custom versions of any package already present in Pulp. By changing the uniqueness constraint to the sha256 one user can have a package from PyPI in their repository and another user upload their own custom version of that package with no conflicts in Pulp. At the repo level, the package filename should still be the uniqueness constraint as the
simpleapi doesn't allow for indexes to have packages of the same name.