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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 do_fish_complete(cli, prog_name):
 """Do the fish completion Parameters cli : click.Command The main click Command of the program prog_name : str The program name on the command line Returns ------- bool True if the completion was successful, False otherwise """

    commandline = os.environ['COMMANDLINE']
    args = split_args(commandline)[1:]
    if args and not commandline.endswith(' '):
        incomplete = args[-1]
        args = args[:-1]
    else:
        incomplete = ''

    for item, help in get_choices(cli, prog_name, args, incomplete):
        if help:
            echo("%s\t%s" % (item, re.sub('\s', ' ', help)))
        else:
            echo(item)

    return True