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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 repository(self, only):
 """Update repositories lists """

        print("\nCheck and update repositories:\n")
        default = self.meta.default_repositories
        enabled = self.meta.repositories
        if only:
            enabled = only
        for repo in enabled:
            if check_for_local_repos(repo) is True:
                continue
            sys.stdout.write("{0}Check repository [{1}{2}{3}] ... "
                             "{4}".format(
                                    self.meta.color["GREY"],
                                    self.meta.color["CYAN"], repo,
                                    self.meta.color["GREY"],
                                    self.meta.color["ENDC"]))
            sys.stdout.flush()
            if repo in default:
                exec("{0}.{1}()".format(self._init, repo))
                sys.stdout.write(self.done)
            elif repo in enabled:
                Initialization(False).custom(repo)
                sys.stdout.write(self.done)
            else:
                sys.stdout.write(self.error)
        print("")   # new line at end
        raise SystemExit()