Errata

In Chapter 11, Section entitled "Packages", the examples show the use of:
from sources import fast, advice
stating that the two files are in the "sources" directory relative to the current working directory. After that, throughout this section, the directories "sources" and "choices" seem to be used; I am suspecting "choices" was first used, then changed to be less confusing in the examples. If I am wrong, please elaborate why "choices" is used as a directory.

In chapter 7, "Typles and lists", under "Modify a tuple" section

t2 = ('Flop,')

should be

t2 = ('Flop',)

in the first two examples in order to generate a tuple. (It is correct in the third).

(No page numbers as I am reading it only on oreilly.com)
Regards

This is the section where you introduce the "walrus" operator, := as of Python 3.8.

The line in the example with the walrus operator is:

if diff := tweet_limit - len(tweet_string) >= 0:

The code snippet "works", but somewhat accidentally. I think the mistake is that the diff variable, instead of containing the value of tweet_limit - len(tweet_string), which is clearly what was intended, instead has the boolean value of True, which in the case of the code by chance gives the expected output. This is because the := operator has the lowest precedence. I believe the line should instead be coded as:

if (diff := tweet_limit - len(tweet_string)) >= 0:

Note from the Author or Editor:
You are correct. The current line resolves to True, which has the integer value 1.

The line should read:

if (diff := tweet_limit - len(tweet_string)) >= 0;

This example function and decorator definition:

>>> @document_it
... def add_ints(a, b):
... return a + b
...
>>> add_ints(3, 5)
Start function add_ints
Positional arguments: (3, 5)
Keyword arguments: {}
Result: 8
8

... should produce this output:

>>> @document_it
... def add_ints(a, b):
... return a + b
...
>>> add_ints(3, 5)
Running function: add_ints
Positional arguments: (3, 5)
Keyword arguments: {}
Result: 8
8

Note the difference in the first line of printed output, namely the incorrect message "Start function add_ints" versus the correct message "Running function: add_ints" respectively.

keyword.kwlist() => keyword.kwlist
kwlist is not a callable function, instead its a attribute of type list.

Note from the Author or Editor:
Fixed during editing. Thanks!

“and then assigning it to a on the left side of the + sign.” should be “and then assigning it to a on the left side of the = sign.”

In Chapter 7: Tuples and Lists, the following example is provided in the "Create with []" introduction to lists:
>>>randomness = ['Punxsatawney", {"groundhog": "Phil"}, "Feb. 2"}

From what I've learned so far, this seems to contain 2 errors: an "unterminated string literal" and "closing parenthesis '}' does not match opening parenthesis '['".

Instead, a correct example might read:
>>>randomness = ['Punxsatawney', {"groundhog": "Phil"}, "Feb. 2"]

Note from the Author or Editor:
All quotes should be single.

In the line of code:

fout = open('relativity', 'xt')]

There is a code error with the extra right brace at the end which when compiled leads to the error:

SyntaxError: unmatched ']'

In ans 12.1 the mystery code is '\U0001f4a9' (pile of poo) but in the Things to Do page (pg 245) the mystery code is '\U0001f984'

In the ans for 12.5, regular expression should have [C|c]. That is, to look for upper and lower case 'c'. The word 'Cows" is missing in the list.

Note from the Author or Editor:
For the 12.1 example, you're right. Try looking up '\U0001f984'.

For the 12.5 example, I specified 'c', which is lower case and technically true, but I didn't say to only look for the lower-case version.