Is it really good?

[Nadav Horesh]

Can someone explain why python does not raise NameError in the first 
test line blow.
I get similar results with Python 2.3a1, wich (obviously) answer False 
instead of 0.

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Python 2.2.2 (#5, Dec 19 2002, 10:39:16)
[GCC 3.2.1] on linux2
Type "copyright", "credits" or "license" for more information.
IDLE 0.8 -- press F1 for help

 >>> 2 == 3 is good
0     # ????????????????????????

 >>> (2 == 3) is good
Traceback (most recent call last):
  File "<pyshell#1>", line 1, in ?
    (2 == 3) is good
NameError: name 'good' is not defined
 >>> 2 == (3 is good)
Traceback (most recent call last):
  File "<pyshell#2>", line 1, in ?
    2 == (3 is good)
NameError: name 'good' is not defined
 >>>

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  Nadav.