cls._inst = type.__new__(cls, *args, **kwargs)

NOW READS:
cls._inst = super(Singleton, cls).__new__(cls, *args, **kwargs)

The 'eggs' parameter passed when trying to instantiate s2...Singleton!

NOW READS:
The 'spam' parameter originally passed when s1 was instantiated has
now been trampled upon by the re-instantiation -- that's part of the
price you pay for having a Singleton!

lines 1, 3 and 5: os.F_GETFL and os.F_SETFL were incorrect.

The code NOW READS:

fl = fcntl.fcntl(fd,fcntl.F_GETFL)
try:
fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NDELAY)
except AttributeError:
fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.FNDELAY)

In this code:

def EndElement(self, name):
'Expat end element event handler'
self.nodeStack[-1].pop( )

the last line is wrong. It should read:

self.nodeStack.pop( )

The source in the book and in the samples zip file is:
rx_headers = re.compile('|'.join(headers), re.IGNORECASE)

but it should be to work properly (it's case sensitive):
rx_headers = re.compile('|'.join(HEADERS), re.IGNORECASE)

Site that is referred to does not exist any more; new site is at
http://www.dabeaz.com/ply/

obj = super(MetaAuto, cls).__call__(cls, *a, **k)
should be changed to
obj = super(MetaAuto, cls).__call__()

AUTHOR'S REPLY:

The reader's observation is ALMOST correct; the proper expression is
neither the one in the book, nor the one he suggests, but rather the
following one:

obj = super(MetaAuto, cls).__call__(*a, **k)

To check this, the reader can run, for example, the following code
(together with what he can find in cb2_20_14_exm_3.py in the zipfile
of all code in the book, available at http://examples.oreilly.com/
9780596007973/cb2_examples.zip ):

class named_recorder(auto_object):
count = 0
events = attr(list)
def __init__(self, name):
self.name = name
def __str__(self):
return '%s: [%s] %s' % (self.name, self.count, self.events)
def record(self, event):
self.count += 1
self.events.append((self.count, event))

r1 = named_recorder('uno')
r2 = named_recorder('dos')
r1.record('zap')
r2.record('zop')
print r1
print r2

This code raises exceptions with both the original formulation (which
wrongly repeats cls) and his suggested one (which wrongly omits *a,
**k), but works as intended with the proper formulation (without
repetition of cls, but WITH *a,**k) given above.