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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 option_chooser(options, attr=None):
 """Given an iterable, enumerate its contents for a user to choose from. If the optional `attr` is not None, that attribute in each iterated object will be printed. This function will exit the program if the user chooses the escape option. """

    for num, option in enumerate(options):
        if attr:
            print("%s: %s" % (num, getattr(option, attr)))
        else:
            print("%s: %s" % (num, option))
    # Add an escape option
    escape_opt = num + 1
    print("%s: I want to exit!" % escape_opt)
    choice = six.moves.input("Selection: ")
    try:
        ichoice = int(choice)
        if ichoice > escape_opt:
            raise ValueError
    except ValueError:
        print("Valid entries are the numbers 0-%s. Received '%s'." % (escape_opt,
                choice))
        sys.exit()

    if ichoice == escape_opt:
        print("Bye!")
        sys.exit()

    return ichoice