try:
    import readline, rlcompleter
    if os.path.exists(histfile):
        readline.read_history_file(histfile)
    readline.parse_and_bind("tab: complete")

    import atexit
    atexit.register(readline.write_history_file, histfile)

    del readline, rlcompleter, atexit

except (ImportError,AttributeError):
    pass

del os,histfile