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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 _list_repos():
 """Lists all the installed repos as well as their last start and finish times from the cron's perspective. """

    if not args["list"]:
        return
    
    #Just loop over the list of repos we have in a server instance. See if
    #they also exist in the db's status; if they do, include the start/end
    #times we have saved.
    from pyci.server import Server
    server = Server(testmode=args["nolive"])
    output = ["Repository           |      Started     |      Finished    | XML File Path",
              "--------------------------------------------------------------------------"]

    dbs = {} if "status" not in db else db["status"]
    fullfmt = "{0:<20} | {1:^16} | {2:^16} | {3}"
    for reponame, repo in server.repositories.items():
        if reponame in dbs:
            start = _fmt_time(dbs[reponame]["start"])
            end = _fmt_time(dbs[reponame]["end"])
        else:
            start = "Never"
            end = "Never"
        output.append(fullfmt.format(reponame, start, end, repo.filepath))

    info('\n'.join(output))