illustration of 0xFFFOO not valid attribute name

>>> a = object()
>>> a.0xaaa
  File "<stdin>", line 1
    a.0xaaa
      ^
SyntaxError: invalid syntax
>>> a.xaa
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'object' object has no attribute 'xaa'
>>>