new_contents: import logging
  import sys
  import os
  
  from common import set_up_logging
  from common import create_sparse_file
  from common import tear_down_disk_images
  from common import print_devices
  
  # doing this before importing blivet gets the logging from format class
  # registrations and other stuff triggered by the import
  set_up_logging()
  blivet_log = logging.getLogger("blivet")
  blivet_log.info(sys.argv[0])
  
  import blivet
  from blivet.size import Size
  
  b = blivet.Blivet()   # create an instance of Blivet (don't add system devices)
  
  # create a disk image file on which to create new devices
  disk1_file = create_sparse_file(b, "disk1", Size(spec="100GB"))
  b.config.diskImages["disk1"] = disk1_file
  
  b.reset()
  
  try:
      disk1 = b.devicetree.getDeviceByName("disk1")
  
      b.initializeDisk(disk1)
  
      pv = b.newPartition(size=Size(spec="50GB"), fmt_type="lvmpv")
      b.createDevice(pv)
  
      # allocate the partitions (decide where and on which disks they'll reside)
      blivet.partitioning.doPartitioning(b)
  
      vg = b.newVG(parents=[pv])
      b.createDevice(vg)
  
      # new lv with base size 5GB and unbounded growth and an ext4 filesystem
      dev = b.newLV(fmt_type="ext4", size=Size(spec="5GB"), grow=True,
                    parents=[vg], name="unbounded")
      b.createDevice(dev)
  
      # new lv with base size 5GB and growth up to 15GB and an ext4 filesystem
      dev = b.newLV(fmt_type="ext4", size=Size(spec="5GB"), grow=True,
                    maxsize=Size(spec="15GB"), parents=[vg], name="bounded")
      b.createDevice(dev)
  
      # new lv with a fixed size of 2GB formatted as swap space
      dev = b.newLV(fmt_type="swap", size=Size(spec="2GB"), parents=[vg])
      b.createDevice(dev)
  
      # allocate the growable lvs
      blivet.partitioning.growLVM(b)
      print_devices(b)
  
      # write the new partitions to disk and format them as specified
      b.doIt()
      print_devices(b)
  finally:
      tear_down_disk_images(b)
      os.unlink(disk1_file)
  
subject: Add an example of creating lvs using growable requests.