def search_for_files(self, files):
        for f in self.filter_files(files):
            pkgname = self._get_package_for_file(f.path)

            # Stores the file
            if pkgname is None:
                self.unknown_files.add(f)
            else:
                if self.packages in pkgname:
                    self.packages[pkgname].add_file(f)
                else:
                    pkg = self._create_package(pkgname)
                    pkg.add_file(f)
                    self.packages[pkgname] = pkg
dataset/ETHPy150Open ViDA-NYU/reprozip/reprozip/reprozip/tracer/linux_pkgs.py/PkgManager.search_for_files/swapped operands of `in`