>>> import msgspec

>>> class A(msgspec.Raw): ...
Traceback (most recent call last):
  File "<python-input-1>", line 1, in <module>
    class A(msgspec.Raw): ...
TypeError: type 'msgspec.Raw' is not an acceptable base type

>>> class A(msgspec.Meta): ...
Traceback (most recent call last):
  File "<python-input-2>", line 1, in <module>
    class A(msgspec.Meta): ...
TypeError: type 'msgspec.Meta' is not an acceptable base type