Errata

After "expressions;" the sentence was changed to read:

"...variables are replaced with their values, and
expression results are echoed back to us:"

now reads:

Four items: indexes 0..3

Mathematically, integers less than 2 are NOT considered prime. Hence, the else
statement after the while loop will still print y as prime even if y contains values
such as 0 or 1, which are NOT prime!

So instead of

...
else:
pirnt y, 'is prime'

It should really be

...
else:
if x == 1: pirnt y, 'is prime'

This is a bug in what the code is supposed to achieve.

AUTHOR: Yes, this is true; but I don't think it's worth patching
(we'd also then have to explain this odd new test in
more details in the text, and it would distract from the
point of the example). However, I will add a note in
the 2nd Edition about this.

This little code snippet demos a Python while loop,
and doesn't claim to be a mathematically precise
definition of prime. It's also wildly inefficient, but
doesn't aim to address better algorithms either.

"..." was put into regular type.

"that exist when the function is called."
now reads:
"that exist immediately after the function is called."

"..." was put into regular type.

"assigns toast and eggs"
now reads:
"assigns toast and ham"

"..." was put into regular type.

"..." was put into regular type.

"..." was put into regular type.

Both "..." were put into regular type.

"..." was put into regular type.

"Just like def, import, and from are executable statements,..."
now reads:
"Just like def, import and from are executable statements,..."

"from mod import" now reads "from mod import *"
(added the star)

changed:
def dostuff();
...
doLastThing();
to:
def doStuff():
...
doLastThing()

Last paragraph, 1st sentence:
"there's no ned" now reads "there's no need"

Example of ord(c) now shows ord('A') value as 65.

The description for the "setattr" built-in function was added:

setattr(object, attributename, value) ->
Assigns value to attribute attributename of object;
raises TypeError if not supported; creates of changes
attribute.

"The character * means ..." now reads "The character + means ..."

os.path.walk('..', test_walk, 'show'
now reads:
os.path.walk('..', test_walk, 'show')

Last line is now indented properly.

This line is now indented properly.

"output.py" now reads "output.txt"

os.system('/usr/bin/mail ... < %(tempfile)s' ... )
now reads:
os.system('/usr/bin/mail ... < %(tempfilename)s' ... )

"text from the string str"
now reads:
"text from the StringIO object str"

line 13 used to read:

stop = string.index(data,'&degv;F',start-1)

It now reads:

stop = string.index(data,'&deg;F',start-1)

"def __init__(self, formdict)"
now reads
"def __init__(self, form)"

paragraph.

from tkinter import mainloop
now reads:
from Tkinter import mainloop

added line:
self.listbox.bind('<ButtonRelease-1>', self.select)
after line 6.

"self-select" now reads "self.select"

string.replace(labelstr, ' '), '')
now reads:
string.replace(labelstr, ' ', '')

The URL for JPython now reads "http://www.jpython.org/".

The URL for JPython/CPython differences now reads "http://www.jpython.org/
docs/differences.html".

added a single quote before "This"

"...L[3:3], the empty insertion point after offset 3" should really be "...L[3:3],
the empty insertion point before offset 3"

Note it is "before", not "after"

AUTHOR: Yes: this is incorrect wording. It should read "at offset 2",
not "after offset 3".

"Before" doesn't really work here nay more than "after".

used to read:
def word(self, index):
return self.words[index]

now reads:

def word(self, index):
return self.words[index] # properly indented!

used to read:
print "Got comment from %(name)s, skipping printing." % vars(data)

now reads:
print "Got comment from %(name)s, skipping printing." %
vars(data)

solution #3:
used to read:
# code from existing program, up to
graphics.fillPolygon(xs, ys, len(xs))

now reads: (left aligned!)

# code from existing program, up to
graphics.fillPolygon(xs, ys, len(xs))