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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 list_all(dev: Device):
 """List all available API calls."""

    for name, service in dev.services.items():
        click.echo(click.style("\nService %s" % name, bold=True))
        for method in service.methods:
            click.echo("  %s" % method.name)