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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 cli(ctx, list, dir, files, project_dir, sayno):
 """Manage verilog examples.\n Install with `apio install examples`"""


    exit_code = 0

    if list:
        exit_code = Examples().list_examples()
    elif dir:
        exit_code = Examples().copy_example_dir(dir, project_dir, sayno)
    elif files:
        exit_code = Examples().copy_example_files(files, project_dir, sayno)
    else:
        click.secho(ctx.get_help())
        click.secho(Examples().examples_of_use_cad())

    ctx.exit(exit_code)