@csev is this related to any recent server updates? Urllib is returning a 403 for this url, but file loads fine in a browser:

http://www.pythonlearn.com/code3/romeo.txt

Code:
https://trinket.io/python3/00dc702e87

I don't remember this happening before.

Comment applies to https://www.py4e.com/html3/13-web

In the sentence, "It is important to include all parent level elements in the findall statement expect for the top level element (e.g., users/user). Otherwise, Python will not find any desired nodes." I think "except" might be what you meant rather than "expect".

First off, I want to thank you for making this content freely accessible. I came to this site through Python for Everyone, and it is very helpful to have a text for the courses.

I have been reading through this version of the text as well as the Python 2 version and I noticed that in word.py , then in Chapter 7 and other examples in the book, the files that are opened in the programs are not explicitly closed. The only place where I saw close mentioned was in order to save a write to a file.

In reading from other sources and from instruction in a Bioinformatics course that I took, it was suggested that as a best practice, you should always explicitly close any files opened by your program, whether or not they were written to, to avoid corruption or inadvertent change.

I am not sure how much of an issue this is, but I wanted to raise it in case it is something that might benefit other learners starting out to get into the habit of writing programs that clean up after themselves when they make file and data calls.

This applies to: https://www.py4e.com/html3/01-intro

Debugging

"When you Python spits out an error or even when ....". I believe it needs to be "When your Python ....."

Thanks
Asal

it is written: " Enter 7, 2, bob, 10, and 4"
you could write: " Enter 7, 2, bob, 10, 4 and done"

This is more of a convenience thing, but would it be possible to add an HTML version to the build server? I'd like my students to be able to get the latest versions of chapters without re-downloading an epub.

Or, even better, can I get permission to set up a build server for my class that builds the latest into an HTML version? I could password-protect it or make sure via the robots.txt it won't get indexed. If we go with this option I can start experimenting with interactive Trinket code blocks for the book

For those of us without PowerPoint it would be nice to get PDFs for https://www.py4e.com/lectures3/

We'll need a benevolent dictator (@csev) edict on this one I think. oauth.py is abandoned and it seems like editing it directly is ill-advised. There is a successor but I haven't dug in to see how similar the API is. Also, it's not a single file, so perhaps more confusing to include in the folder and have users import locally.

Backing up, how should the twitter examples be revised? There are some twitter-specific modules out there but they may be too high level for the chapter's goals. Rewriting them to use oauth2 seems like a good way forward but just wanted to check before heading down that road. Some of the changes may be extensive (since Twitter also revised its API in the meantime) and may demand text tweaks.

Dear Prof Sev,

The code for twspider.py shows that the database created is 'spider.sqlite'.

In the chapter text immediately below the code, the file is described as 'spider.sqlite3'.

I expect that these should both be consistent, either both one or the other?

https://www.py4e.com/html3/15-database

There are two typos in the HTML book https://www.py4e.com/html3/12-network
They are located in the title and the third sentence.

1. HyperText Transfer Protocol - HTTP
   The first "t" should be lowercase:
   Hypertext Transfer Protocol - HTTP
   https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol

2. In the sentence, "The network protocol that powers the web is actually quite simple and there is built-in support in Python called sockets..." sockets should be socket.
   This is how it is mentioned in the reference.
   https://docs.python.org/3.7/library/socket.html

If a change is made to db2.py in the code3/ folder, subsequent travis checks fail because the database + table don't exist/exist yet.

Hi, I am MinSeok who is a newbie of Python..

I found one bug on code3/urlregex.py, so I am reporting below.
There were making ctx object but it would never use it later.
So this source code won't work because of error on urlopen() function to try to cconnect https without ctx of ssl.
So, Code will have to modify like below to work well.

-- Before
html = urllib.request.urlopen(url).read()

-- After
html = urllib.request.urlopen(url, context=ctx).read()

I am sorry for paying your attention of this issue, If someone already reported it.

I hope it will help you make your nice Python textbook and videos.
Sincerely,
MinSeok.

This is an initial list of what's working with & without errors. The more complicated files (those in subdirectories, those that use sqlite dbs, twitter, etc) deserve a second look, executing the code in a specific order.

• ./argfile.py
• ./argtest.py
• ./avelist.py
• ./avenum.py
• ./average.py
• ./celsius.py
• ./copytildone.py
• ./count1.py
• ./count2.py
• ./count3.py
• ./curl1.py
• ./curl2.py
• ./curl3.py
• ./db1.py
• ./db2.py
• ./egg.py
• ./emaildb.py
• ./fahren.py
• ./geodata/geodump.py
• ./geodata/geoload.py # NameError: name 'buffer' is not defined
• ./geojson.py
• ./geoxml.py # program doesnt terminate but is fine
• ./gmane/gbasic.py
• ./gmane/gline.py
• ./gmane/gmane.py # needs bytes conversion
• ./gmane/gmodel.py
• ./gmane/gword.py
• ./gmane/gyear.py
• ./grade.py
• x ./graphics/graphics.py # TODO; I'm headless
• x ./graphics/histogram.py # TODO; I'm headless. also TabError: inconsistent use of tabs and spaces in indentation
• ./greet.py
• ./grep.py
• ./hidden.py
• ./json1.py
• ./json2.py
• ./largest.py
• ./mailcount.py
• ./mailtop.py
• ./oauth.py # This will need to be updated- uses depricated sha
• ./open.py
• ./pagerank/BeautifulSoup.py # Needs latest version ImportError: No module named 'sgmllib'
• ./pagerank/spdump.py
• ./pagerank/spider.py # Needs beautiful soup bump & check
• ./pagerank/spjson.py
• ./pagerank/sprank.py
• ./pagerank/spreset.py
• ./pals.py
• ./pay.py
• ./pay2.py
• ./pay3.py
• x ./pythonweb/webserver.py # SyntaxError: Missing parentheses in call to 'print'
• ./re01.py
• ./re02.py
• ./re03.py
• ./re04.py
• ./re05.py
• ./re06.py
• ./re07.py
• ./re08.py
• ./re09.py
• ./re10.py
• ./re11.py
• ./re12.py
• ./re13.py
• ./re14.py
• ./roster/roster.py # NameError: name 'roster_data' is not defined
• ./search1.py
• ./search10.py
• ./search2.py
• ./search3.py
• ./search4.py
• ./search5.py
• ./search6.py
• ./search7.py
• ./search8.py
• ./search9.py
• ./sequence.py
• ./socket1.py
• ./socket2.py
• ./soft.py
• ./spamave.py
• ./tracks/tracks.py
• ./twdump.py # The twitter examples need an oauth bump, maybe more
• ./twfriends.py # Also plenty of Also TypeError: key: expected bytes or bytearray, but got 'str'
• ./twitter1.py
• ./twitter2.py
• ./twjoin.py
• ./twspider.py
• ./twtest.py
• ./twurl.py
• ./txtcheck.py
• ./txtcheck2.py
• ./txtcheck3.py
• ./txtcount.py
• ./txtdelete.py
• ./txtmd5.py
• ./txtsize.py
• ./urljpeg.py
• ./urllib1.py
• ./urllib2.py
• ./urllink2.py # bs4.FeatureNotFound: Couldn't find a tree builder with the features you requested: lxml. Do you need to install a parser library?
• ./urllink3.py
• ./urllinks.py
• ./urlregex.py
• ./urlwords.py
• ./whathour.py
• ./wikigrade.py
• ./wordlist.py
• ./words.py
• ./xml1.py
• ./xml2.py

Upon running sample code twitter1.py and it fails on this error:

$ python3 twitter1.py

Enter Twitter Account:mytwitter
Traceback (most recent call last):
File "twitter1.py", line 20, in
{'screen_name': acct, 'count': '2'})
File "/Users/xxxxph/PycharmProjects/xxxxPy/twurl.py", line 10, in augment
consumer = oauth.OAuthConsumer(secrets['consumer_key'],secrets['consumer_secret'])
AttributeError: module 'oauth' has no attribute 'OAuthConsumer

any suggestions, the same error occurs if I try with oauth2

![Relationships Between Tables](height=3.5in@figs2/twitter)"

![Connecting Tables Using JOIN](height=3.5in@figs2/join)

I assume the data should mimic the one in xml2.py, so the suggestion is for the 2nd item, make the name tag "Brent"

Formatting for the exercise 4 header in chapter 6 is off in the HTML version. It just needs ... instead of **... .

I should be able to lend a hand with the conversion. Looking at the repo and commit history, it's not immediately apparent what needs attention. The TODO file gives a decent overview of what needs to be done but not, for instance, which files have been checked already and which still have issues.

Everyone's got their own product management prefs. @csev: you're the guru for this repo. Prefs?

I've seen checklist issues work for smaller stuff. For example:

• This is a filename that needs conversion
• This is a filename that is done.

The downside is they must be manually checked off by a committer.

I've also seen one issue per todo work. A nice thing is that the issues can then be closed via the PR they address. Also, they are very easy for contributors to pick up and knock out.

Happy to chat synchronously if that's helpful. Once some work is scoped I should be able to contribute every few days as I prep my course.

Don't know the Markup required to fix, it looks like it should highlight the code as Python.
https://py4e.com/html3/08-lists

Debugging
1.

It is tempting to write list code like this: ~~ {.python} t = t.sort() # WRONG! ~~

The markup looks the same as the other code snippets when editing
py4e/edit/master/book3/08-lists.mkd

A student of mine found a erroneous code sample in Chapter 7 - both in the html and the associated .py file. (https://www.py4e.com/code3/search7.py)

Here is what it says in the code:

fname = input('Enter the file name: ')
try:
    fhand = open(fname)
except:
    print('File cannot be opened:', fname)
    exit()
count = 0
for line in fhand:
    if line.startswith('Subject:'):
        count = count + 1
print('There were', count, 'subject lines in', fname)

-The problem with this is: if the file name is wrong or the file cannot be read (i.e., the code block in try fails and it goes to except), it still tries to do the remaining operations (reading the file in the for loop) and throws an error. The exit() somehow did not work. That whole part should have been in the try block itself. It was okay for us, as the student could ask me, but I guess for people learning on their own, this could confuse them. Please edit this.

Just discovered this and thought I'd drop a link for consideration. Haven't dug in too deeply but seems like this would give a slick paginated feel to the epub and make it readable without installing a reader https://github.com/joseph/Monocle

Quick example of what o book looks like in it: http://monocle.inventivelabs.com.au/books/dubliners

Also seems possible that trinket embeds and any other HTML would work in this view.

(found during my search for a good Chrome epub reader)

As time advances, newer versions of python will be released. It's nice to know that the behavior of the code samples or assignments doesn't change or if it does, it can be quickly isolated and fixed.
Maybe this is overkill, what do you think?

I was a little sloppy with some commits and the pdf and epub made it in. I'm happy to fix conflicts I cause but wondering if it might be a good idea to gitignore them since they're build products?

Some of the materials for this book reference Python 3.0. I think there's one too many significant figures in there. It'd be more correct to say "Python 3"; Python 3.0 has been obsolete since the release of Python 3.1 on June 27th, 2009 :)

For the official supported subversion of the language, I think it'd be best to pick a recommended subversion such as 3.4 or 3.5 and note it in the preface or introduction. "Will work with Python 3.X or later" or etc. We may be compatible with Python 3.0 but someone should probably[1] go through in a venv and check. Major versions are (theoretically) backwards compatible so whatever the subversion is we should be good for all future 3.Xs. bs4 or some other third party module is likely to be the limiting factor on this- they often like to use the latest.

[1] - "someone should probably" means "I'll do this eventually if no one else does, but I hope someone else does"

"The first five locations are already in the database and so they are skipped."
=>
"The first six locations are already in the database and so they are skipped."

Please correct me if I'm missing something, but I think some code examples in chapter 14 is not accurate.

e.g.
in party5.py
the "x = 0" and "name = """ is class variables (https://docs.python.org/3.7/tutorial/classes.html#class-and-instance-variables), I think it's clearer to remove them and add self.x = 0 in the constructor.

In PY4E - Chapter 13, there are two "phone" node in the the picuture of "A Tree Representation of XML", the last "phone" node should be "email" node.

Cannot push a fix branch to the repo, the diff:

--- a/book3/02-variables.mkd
+++ b/book3/02-variables.mkd
@@ -649,7 +649,7 @@ at you:

 for word in words:
-    print word
+    print(word)
 

Exercises
Exercise 2: Write a program that categorizes each mail message by which day of the week the commit was done. To do this look for lines that start with "From", then look for the third word and keep a running count of each of the days of the week. At the end of the program print out the contents of your dictionary (order does not matter).

should be comment?

In the 'Tuple Assignment' section of Chapter 10 there are 3 code examples where the example shows operations on a list rather than a tuple.

First:

>>> m = [ 'have', 'fun' ]
>>> x, y = m
>>> x
'have'
>>> y
'fun'
>>>

should be:
>>> m = ( 'have', 'fun' )
>>> x, y = m
>>> x
'have'
>>> y
'fun'
>>>

Second:

>>> m = [ 'have', 'fun' ]
>>> x = m[0]
>>> y = m[1]
>>> x
' have'
>>> y
'fun'
>>>

should be:
>>> m = [ 'have', 'fun' ]
>>> x = m[0]
>>> y = m[1]
>>> x
' have'
>>> y
'fun'
>>>

Third(and last):

>>> m = [ 'have', 'fun' ]
>>> (x, y) = m
>>> x
'have'
>>> y
'fun'
>>>

should probably be:
>>> m = [ 'have', 'fun' ]
>>> (x, y) = m
>>> x
'have'
>>> y
'fun'
>>>

I say probably because technically this does show use of a tuple in an assignment, but I suspect the intent was to show a tuple on both sides of the assignment operator.

As described in #63, we can automatically include the text of code3 files in the text of the book using \VerbatimInput{<filename>}. This now needs to happen for each chapter.

• Chapter 1
• Chapter 2
• Chapter 3
• Chapter 4
• Chapter 5
• Chapter 6
• Chapter 7
• Chapter 8
• Chapter 9
• Chapter 10
• Chapter 11
• Chapter 12
• Chapter 13
• Chapter 14
• Chapter 15

"After the DELETE is performed, we also call commit() to force the data to be removed from the database."

That's not what's shown in code3/db2.py

Under: Multiple assignment with dictionaries

Can drop the "list" in:
for key, val in list(d.items()):
print(val, key)

suggested form:
for key, val in d.items():
print(val, key)

Dear Prof Sev,

The code in party5.py on the Chapter 14 page initiates 'Sally' and 'Jim' but then shows the code as printing out Sally, then Sally-Party, then Jim and Jim-party.

According to the code, Sally and Jim should initiate first, but according the the box that shows the output, Sally initiates, then parties, then Jim initiates, then Jim parties.

Things I've encountered as one-offs that I'll Ctrl-f for in all chapters:

• remove all u'unicode strings' since Python 3 is unicode by default (esp chapter 14)
• make sure all markdown links have http:// in the URL
• explain u' vs b' in Python 2 & 3 at the appropriate points. The python docs have a great explanation of urllib here:

Note that urlopen returns a bytes object. This is because there is no way for urlopen to automatically determine the encoding of the byte stream it receives from the http server. In general, a program will decode the returned bytes object to string once it determines or guesses the appropriate encoding.

• Bad hyphens and any other character problems. Just saw this bad hyphen in chapter 12:

There may be other problem characters. Once they're found it's an easy job to go replace them with the right char.

Line 567-570:

For most systems, there are applications to convert from one format to
another. You can find them (and read more about this issue) at
wikipedia.org/wiki/Newline. Or, of course,
you could write one yourself.

I think the link should be absolute, otherwise it's opening:
https://www.py4e.com/html3/wikipedia.org/wiki/Newline
and the page does not exist.

I've started translating Python for Everybody book to Russian. Could you setup your build server to produce Russian version of PY4E?

Should intro be Ch 0 or Ch 1? If 0, can I rename the files to match? Trying to avoid confusion.

Several chapters have exercise numbering that's off.

Edit: This would be a quick fix for a new contributor to tackle! Ctrl-F for Exercise and make sure they count up correctly.

• Chapter 1
• Chapter 2
• Chapter 3
• Chapter 4
• Chapter 5
• Chapter 6
• Chapter 7
• Chapter 8
• Chapter 9
• Chapter 10
• Chapter 11
• Chapter 12
• Chapter 13
• Chapter 14
• Chapter 15

Sorry, There is something that went wrong with your code in the program that checks the unique word and count their total number of frequency they appear.

You have written:
name = input('Enter file:')

I think it should be
name = input(print('Enter file:'))

Thanks for your support.

word *in* words*:*\ *print* word
perhaps should be
*for* word *in* words*:*\ *print* word

In Exercise 4
1 + 2 \* 5
The * is escaped and perhaps should just be
1 + 2 * 5

I've started using Travis CI for my class website and it's pretty great. Wondering if tests for this repo would be a good idea? Would ensure that PRs don't break builds. Downside: Waiting a few minutes when a PR gets submitted to see if it passes.

Initially it could just check that book.sh builds with no errors but eventually could check the html version, website, etc. https://github.com/gjtorikian/html-proofer or something similar could check for dead links, etc.

Is there an official styling guide?

Seeing as the book is aimed at beginners, I would like the code samples to be as clear and beginner-friendly as possible.

Specifically, I would like to change all one liners such as:
if re.search(search, line): count = count + 1
into

if re.search(search, line):
    count = count + 1

Any thoughts?

This will take the figures from book/figs2 and redraw them in omnigraffle and put the omnigraffle files in figures and the SVG / EPS files in the folder images. There is already a pda figure that has been converted.

• Chapter 1
• Chapter 2
• Chapter 3
• Chapter 4
• Chapter 5
• Chapter 6
• Chapter 7
• Chapter 8
• Chapter 9
• Chapter 10
• Chapter 11
• Chapter 12
• Chapter 13
• Chapter 14
• Chapter 15

For \VerbatimInput blocks it would be spiffy to have the filename listed above the code somehow for easy reference.

the .format method is replacing the % operator, which will eventually be deprecated. Python 3 supports both, so we should cover both in Chapter 6.

I'll try to add this in the next few weeks if I can - teaching a summer course.

Adding ~~~~ {.python} and ~~~~ {.python trinket} (Edit: typo; it needs to be ~~~~ {.python .trinket}) to code blocks to invoke pandoc's built-in syntax highlighting and allow optional trinketization in the HTML output. The trinket (and anything else in the braces) is either ignored or added as a class in HTML output, meaning non-trinketized versions will be unaffected. My scripts use it to know when code blocks can/should be made interactive vs. when they're a fragment that should only be highlighted.

I'm also converting indent-based code blocks to fenced for completeness though it of course won't affect the output.

Documenting progress here:

• Chapter 1
• Chapter 2
• Chapter 3
• Chapter 4
• Chapter 5
• Chapter 6
• Chapter 7
• Chapter 8
• Chapter 9
• Chapter 10
• Chapter 11
• Chapter 12
• Chapter 13
• Chapter 14
• Chapter 15

The start of Chapter 10 - Tuples has a "Fun fact" footnote:

A tuple^[Fun fact: The word "tuple" comes from the names given to sequences of numbers of varying lengths: single, double, triple, quadruple, quituple, sextuple, septuple, etc.]

Here quituple should be quintuple.