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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_exclusions(self):
 """ Return a collections.Sized collections.Container of paths to be excluded for single_version_externally_managed installations. """

        all_packages = (
            pkg
            for ns_pkg in self._get_SVEM_NSPs()
            for pkg in self._all_packages(ns_pkg)
        )

        excl_specs = product(all_packages, self._gen_exclusion_paths())
        return set(starmap(self._exclude_pkg_path, excl_specs))