Errata

In the Python 3.0 changes section, this bullet item describes the demise of the backquotes expression, but seems to show this using straight quotes. Backquotes are formatted properly later, on pages 96 and 136.

Also in the Python 3.0 section, a comma in program code was deleted, also somewhere in the production process. The "except name value" should read as "except name, value" as described later in the book (see pages 583, 594, 612, and 614).

Python mplements should be: Python implements

...error text omittted... should be: ...error text omitted...

No space between "of" and "small" in the line: "...mutable sequence ofsmall integers..."

# This works: can chage mutables inside should be: # This works: can change mutables inside

In the very first sentence on this page, the "rwords" should be "words"

...it doesn't care what SYS.SYTDOUT is, only... should be: ...it doesn't care what SYS.STDOUT is, only...

In 2 spots of this section, I transposed the I1/I2 and C2/C3 variable names. The typo should be apparent from the surrounding text, but it could also be a bit confusing given the introductory nature of this section. Specifically: in this section's very first sentence, "C2.w" should be "C3.w"; in the last sentence of this section's second paragraph, "C3.w(I1)" should be "C3.w(I2)."

There is a case typo in the commented-out line here. It should read "#print C.m.X", with the uppercase

"Write a class called Mylist..." According to the name convention, Mylist should be MyList. The answer to this question (p664-665) also use MyList.

Note from the Author or Editor:
I posted a fix for this in the errata list for the 4th Edition, page 817 (the same names are used in that edition). In short, yes: in questions #2 and #3, "Mylist" and "MylistSub" should be changed to "MyList" and "MyListSub" so that they match the names used in the solutions to these exercises in Appendix B. Not a major issue, but worth a fix.

It reads: "Mixing from into the same statement ...." but shoud be: "Mixing finally into the same statement ...."

Note from the Author or Editor:
This is a known errata, and has been fixed in later printings of the book. Please see the following page, where I keep track of book corrections, and post general notes about both the book and recent changes in Python: http://www.rmi.net/~lutz/lp3e-updates.html

"A class must manually call the __init__ method in a superclass if it defines an __init__ constructor of its own" Am I right in guessing you mean that the subclass constructor does not automatically call its superclass constructor(s)? I'm guessing many readers would finish the sentence believing that an exception will be thrown if they forget to code a superconstructor call.

Note from the Author or Editor:
No, the second half of this sentence (left out of this post): "but it also must still kick off the superclass’s construction code." means you need to make the call only if you need the superclass's constructor code to be run too. This is also well documented earlier in the Chapter itself -- see especially section "Calling Superclass Constructors" where this is made very clear-- and the exercises are just a review of this material. Still, the language here is a bit loose, and reflects some editing made during production. To clarify, let's change the first sentence of answer #3 now on Page 708 to read as follows: "3. A class must manually call the __init__ method in a superclass if it defines an __init__ constructor of its own and still wants the superclass’s construction code to run." (I'll repost this to the 4th Ed's list, since this is really about that).

"picking" should be "pickling".

Note from the Author or Editor:
Yes -- change "by picking or shelving" to "by pickling or shelving", at the end of line 4 of the sidebar that is now on Page 748 in the May 2011 reprint. (Type changed: this is hardly a serious technical mistake!)

"I ran this in a shell widow with Python 3.0. " I think you mean "window" in "widow."

Note from the Author or Editor:
[This is actually a 4th Edition typo, but went unfixed till now because it was filed against the 3rd Edition.] Yes -- please fix as described: "widow" should be "window". This appears on Page 842 in the latest printing I've seen (Nov 2011), at the start of paragraph 4.