adding a disk code sketch

sketch_add_disk.py

    from pyVmomi import vim
    
        spec = vim.vm.device.VirtualDiskSpec()
        spec.operation = vim.vm.device.VirtualDeviceSpec.Operation.add
        spec.fileOperation = vim.vm.device.VirtualDeviceSpec.FileOperation.create
        spec.device = vim.vm.device.VirtualDisk(
                capacityInBytes=capacity_bytes,
                capacityInKB = capacity_kb,
                connectable = vim.vm.device.VirtualDevice.ConnectInfo(
                    startConnected = True,
                    connected = True
                ),
                backing = vim.vm.device.VirtualDisk.FlatVer2BackingInfo(
                     thinProvisioned = True,
                     diskMode = vim.vm.device.VirtualDiskOption.DiskMode.persistent,
                     fileName = disk_conf.path,
                )
            )

        spec.device.key = device_key # calculate or look up some how
        spec.device.controllerKey = key # calculate or look up some how
        spec.device.unitNumber = unit # calculate or look up some how

  
        spec_list = [spec]
        reconfig_spec = vim.vm.ConfigSpec(name=vm_name, deviceChange=spec_list)
        vm.ReconfigVM_Task(spec=reconfig_spec)

        #SEE also:
        #       https://github.com/vmware/pyvmomi-community-samples/blob/master/samples/add_disk_to_vm.py