def METHOD_NAME(self):
    """
    Call CreateComputeEnvironment with a nonexistent instance type.
    For more information on why this would be done, see the docstring for
    _get_supported_instance_types_create_compute_environment_error_message.
    """
    nonexistent_instance_type = "p8.84xlarge"
    self._client.create_compute_environment(
        computeEnvironmentName="dummy",
        type="MANAGED",
        computeResources={
            "type": "EC2",
            "minvCpus": 0,
            "maxvCpus": 0,
            "instanceTypes": [nonexistent_instance_type],
            "subnets": ["subnet-12345"],  # security group, subnet and role aren't checked
            "securityGroupIds": ["sg-12345"],
            "instanceRole": "ecsInstanceRole",
        },
        serviceRole="AWSBatchServiceRole",
    )