Not all Python object types are supported; in general, only objects whose value
is independent from a particular invocation of Python can be written and read by
-this module. The following types are supported: ``None``, integers,
-floating point numbers, strings, bytes, bytearrays, tuples, lists, sets,
-dictionaries, and code objects, where it should be understood that tuples, lists
-and dictionaries are only supported as long as the values contained therein are
-themselves supported; and recursive lists and dictionaries should not be written
-(they will cause infinite loops).
+this module. The following types are supported: booleans, integers, floating
+point numbers, complex numbers, strings, bytes, bytearrays, tuples, lists, sets,
+frozensets, dictionaries, and code objects, where it should be understood that
+tuples, lists, sets, frozensets and dictionaries are only supported as long as
+the values contained therein are themselves supported; and recursive lists, sets
+and dictionaries should not be written (they will cause infinite loops). The
+singletons :const:`None`, :const:`Ellipsis` and :exc:`StopIteration` can also be
+marshalled and unmarshalled.
There are functions that read/write files as well as functions operating on
strings.