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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 matrix(ctx, scenario_name, subcommand):
 # pragma: no cover """ List matrix of steps used to test instances. """


    args = ctx.obj.get('args')
    command_args = {
        'subcommand': subcommand,
    }

    s = scenarios.Scenarios(
        base.get_configs(args, command_args), scenario_name)
    s.print_matrix()