fix typo: 'frozonset' -> 'frozenset'
@@ -46,7 +46,7 @@ with custom properties and validation.
: allows `list`, `tuple`, `set`, `frozenset`, or generators and casts to a set;
see `typing.Set` below for sub-type constraints
-`frozonset`
+`frozenset`
: allows `list`, `tuple`, `set`, `frozenset`, or generators and casts to a frozen set;
see `typing.FrozenSet` below for sub-type constraints
