Ensure insertion order of Python dict

    for call in add_partition_calls:

      add_partition(*call)

  else:

    # When calling avbtool make_vbmeta_image, it uses the `partitions`

    # dictionary to include the options for --include_descriptors_from_image.

    # The vbmeta image is different if the order of the

    # --include_descriptors_from_image changes. As the images are generated

    # parallelly and entries are added on completion of image creation,

    # this `partitions` dict might be indeterministic as the order of

    # completion of image creation cannot be predicted.

    # To address this issue, add keys to the dict `partitions` with null values

    # in the order they are listed in the variable `add_partition_calls`, and

    # then the values are updated by `add_partition` keeping the order of the

    # items. This ensures generated vbmeta.img is the same for the same input.

    for call in add_partition_calls:

      if call[1]:

        partitions[call[0]] = None

    with ThreadPoolExecutor(max_workers=len(add_partition_calls)) as executor:

      for future in [executor.submit(add_partition, *call) for call in add_partition_calls]:

        future.result()