code: def upgrade(self, only):
          
          repositories = self.meta.repositories
          if only:
              repositories = only
          for repo in repositories:
              changelogs = "{0}{1}{2}".format(self.log_path, repo,
                                              "/ChangeLog.txt")
              if os.path.isfile(changelogs):
                  os.remove(changelogs)
              if os.path.isdir(self.lib_path + "{0}_repo/".format(repo)):
                  for f in (os.listdir(self.lib_path + "{0}_repo/".format(
                          repo))):
                      files = "{0}{1}_repo/{2}".format(self.lib_path, repo, f)
                      if os.path.isfile(files):
                          os.remove(files)
                      elif os.path.isdir(files):
                          shutil.rmtree(files)
          Update().repository(only)
docs: Remove all package lists with changelog and checksums files
          and create lists again