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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 install_completion(ctx, attr, value):
 # pragma: no cover """Install completion for the current shell."""

    import click_completion.core

    if not value or ctx.resilient_parsing:
        return value

    shell, path = click_completion.core.install()
    click.secho(
        '{0} completion installed in {1}'.format(shell, path), fg='green'
    )
    ctx.exit()