fix: Add reference to NoneType in the astx scope (#280)

Author: xmnlab

libs/astx/src/astx/__init__.py

@@ -173,6 +173,7 @@
     Integer,
     ListType,
     NandOp,
+    NoneType,
     NorOp,
     NotOp,
     Number,
@@ -322,6 +323,7 @@ def get_version() -> str:
     "MutabilityKind",
     "NamedExpr",
     "NandOp",
+    "NoneType",
     "NorOp",
     "NotOp",
     "Number",

libs/astx/src/astx/types/base.py

@@ -18,5 +18,5 @@ class AnyType(DataType):
 
 @public
 @typechecked
-class NoneType(DataType):
+class NoneType(AnyType):
     """NoneType data type expression."""