For example:

>>> from enum import *
>>> class E(IntEnum):
...     x = 1
... 
>>> dir(E)
['__class__', '__doc__', '__members__', '__module__', 'x']
>>> E.from_bytes
<built-in method from_bytes of EnumType object at 0x559d47415ce0>
>>> E.to_bytes
<method 'to_bytes' of 'int' objects>
>>> E.numerator
<attribute 'numerator' of 'int' objects>
>>> E.__add__
<slot wrapper '__add__' of 'int' objects>

There are methods and attributes inherited from int, but they are not shown in dir(). As result they are absent in help() and completion does not work for them.