def _get_num_gpus_on_instance(instance_type_info):
    """
    Return the number of GPUs attached to the instance type.

    instance_type_info is expected to be as returned by DescribeInstanceTypes:
    {
        ...,
        "GpuInfo": {
            "Gpus": [
                {
                    "Name": "M60",
                    "Manufacturer": "NVIDIA",
                    "Count": 2,
                    "MemoryInfo": {
                        "SizeInMiB": 8192
                    }
                }
            ],
        }
        ...
    }
    """
    return sum([gpu_type.get("Count") for gpu_type in instance_type_info.get("GpuInfo").get("Gpus")])