object().__dict__

[Pavel Volkov]

There are some basics about Python objects I don't understand.
Consider this snippet:

>>> class X: pass
... 
>>> x = X()
>>> dir(x)
['__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', 
'__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', 
'__init__', '__le__', '__lt__', '__module__', '__ne__', '__new__', 
'__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', 
'__str__', '__subclasshook__', '__weakref__']
>>> x.foo = 11

And now I want to make a simple object in a shorter way, without declaring 
X class:

>>> y = object()
>>> dir(y)
['__class__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', 
'__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__le__', 
'__lt__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', 
'__setattr__', '__sizeof__', '__str__', '__subclasshook__']
>>> y.foo = 12
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'object' object has no attribute 'foo'

The attribute list is different now and there's no __dict__ and the object 
does not accept new attributes.
Please explain what's going on.