class shelve.Shelf(dict, protocol=None, writeback=False, keyencoding='utf-8')
A subclass of collections.abc.MutableMapping which stores pickled values in the dict object.
By default, version 3 pickles are used to serialize values. The version of the pickle protocol can be specified with the protocol parameter. See the pickle documentation for a discussion of the pickle protocols.
If the writeback parameter is True, the object will hold a cache of all entries accessed and write them back to t