Registry: pass along objects from one understand method to the next about dxtbx HOT 9 OPEN

  _cache_controller = dxtbx.filecache_controller.simple_controller()
  @classmethod
  def get_cache_controller(cls):
    return cls._cache_controller

# A shared caching layer for file-like objects.
# pseudo_file objects can be used as drop-in replacements for actual file
# handles to provide a transparent caching layer to avoid reading multiple
# times from disk or network.
#
# To create a pseudo_file instance, encapsulate a 'real' file handler
# inside a lazy cache object:
#   from dxtbx.filecache import lazy_file_cache
#   cache = lazy_file_cache(open(filename, 'rb'))
#
# Finally use a reference to the cache object to create one or many pseudo_file
# instances:
#   fh1 = cache.open()
#   from dxtbx.filecache import pseudo_file
#   fh2 = pseudo_file(cache) # equivalent
#   fh3 = pseudo_file(cache)
#   ...
#
# Each pseudo_file instance can then be treated as a proper read-only
# file handle, but will benefit from a shared cache:
#   with cache.open() as fh:
#     fh.read(100)
#     fh.readline()
#     fh.seek(500)
#     fh.read()
#     fh.readlines()
#     fh.close()
#
# To flush the cache and free the memory you can use
#     cache.close()
# This will drop the cache when all associated file handles are closed.
# To instantly drop the cache you can use
#     cache.force_close()
# Any further access attempts will then result in an exception.