code: def iterpackages(self):
          
          pkgdir = os.path.join(self._path, self.PKG_DIR)
          if not os.path.isdir(pkgdir):
              return
          for team in sub_dirs(pkgdir):
              for user in sub_dirs(self.team_path(team)):
                  for pkg in sub_dirs(self.user_path(team, user)):
                      pkgpath = self.package_path(team, user, pkg)
                      for hsh in sub_files(os.path.join(pkgpath, PackageStore.CONTENTS_DIR)):
                          yield self.get_package(team, user, pkg, pkghash=hsh)
docs: Return an iterator over all the packages in the PackageStore.