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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:
 async def command(dev, service, method, parameters):
 """Run a raw command."""

    params = None
    if parameters is not None:
        params = ast.literal_eval(parameters)
    click.echo("Calling %s.%s with params %s" % (service, method, params))
    res = await dev.raw_command(service, method, params)
    click.echo(res)