FrontMatter

xxiv :: Optional Sections : edit to 2nd paragraph: "... can skip the first chapter and go straight to Chapter 2... absorb Python and be off to the races."

Chapter 1

Chapter 2

>>> print "%s is number %d!" % ("Python", 1)
Python is number 1!

27 :: 2.2 : reword parenthesized segment in the 3rd sentence to: (Use the string.atoi() function for Python versions older than 1.5.)

27 :: 2.3 : code does not accurately reflect interpreter; change code to:

>>> # one comment
... print 'Hello World!'   # another comment
Hello World!

32 :: 2.8 : "aLlist" at bottom of first interactive example should be changed to "aList"

35 :: 2.12 : "loop #5" of interactive example should be deleted

36 :: 2.13 : In the final print statement, the items to be printed are missing their opening parenthesis. It should be:

...    (who, ((what + ' ') * 4))

40 (top) :: 2.16 : first sentence from preceding page should be changed to read: "... declared before they can be called." (Functions do not have types in Python.)

44 (top) :: 2.17 : Interactive example is missing "My name is..." as in:

>>> foo2.showname()
Your name is Jane Smith
My name is __main__.FooClass

Chapter 3

68-71 :: 3.6 : Example (not Listing) 3.1 : On line 25, there is a cryptic reference to sys.exc_info()[1] and no explanation on p. 71. As you will discover, sys.exc_info() is a function which returns a list containing an exception class, an exception object, and a traceback object. The [1] simply refers to the 2nd item (exception object) of the list. It is no different than an operation similiar to:

>>> aList = [123, 'xyz', 45.67]
>>> print aList[1]
>>> xyz

73 :: 3.7 : Exercise 3-8 : 1st sentence should refer to string.find() the function, not module

Chapter 4

77 :: 4.2 : Core Note : "... wrapping a type around a Python class..." should be "... wrapping a class around a Python type...." Also, the last sentence should say, "See Sections 13.15 and 13.16," not 13.18.

84-85 :: 4.5.2 :: Examples 1, 2, 3 and Figures 4-1 and 4-2 : Python caches low integers (and some strings), so using integer 4 in these examples (and in the figures) may result in the same object being referenced. If this is your experience, change the integers to floats and try again, i.e.,

>>> foo1 = 4.0
>>> foo2 = 1.0 + 3.0
>>> id(foo1)
134668004
>>> id(foo2)
134667956

86 :: 4.5.2 :: This "Core Note" sidebar is missing at the end of section 4.5.2:

CORE NOTE: Interning
Smaller integers, identifier names, and shorter strings which are similar to identifier names which may be used often in the code will be cached internally, a process known as interning. If an object is interned, then multiple references to such objects will be identical. (In other words, common objects such as these will only be created once and shared, otherwise it is a waste of resources to have multiple objects with the same value which are created and referenced often.)

If you have tried the example in this section with your interpreter, you will discover that "foo1" and "foo2" would refer to the same object (when you use a is b or id(a) == id(b))! Don't worry if you get that... it is not a mistake by the interpreter. Change the integer 4 to float 4.0 and see if you get the expected result. Also see section 14.3.6 for more about interning.

91 :: 4.6.3 : ">>> type(Abc)" of interactive example assumes a declared class named Abc

Chapter 5

107 :: 5.4 : separate the 2nd and 3rd to last complex numbers in the final line of Section 5.4. 0+1j and 9.80665-8.31441J are are different complex numbers.

109 :: 5.5.1 : text reference should be the Python Language Reference Guide.

110 :: 5.5.1 : output on the second interactive example should be 999998000001L, not 99999B000001L.

118 :: 5.6.2 : ndig is the optional second argument, not third.

Chapter 6

134 :: 6.1.1 : Figure 6-2 : There should be no space between sequence and [:] in the caption.

145 :: 6.3.2 : Core Tip : First print statement should be indented in the while loop.

147 :: 6.4.1 : In the 2nd sentence, "pack" should really be "lack."

152 :: 6.4.2 : There should be no "our RE matched:" strings in either of the statements in the interactive output at the end of this section.

153 :: 6.4.3 : There should be no space between ur and the quoted Hello World string.

155 :: 6.6 : Table 6.6 : string.alnum is misspelled with a 1 rather than an "L".

176 :: 6.11.2 : There should be no string 'park' in the concatenation of str_list + num_list in the output near the bottom of the page.

182 :: 6.13 : Table 6.10 : The description for the pop() list method is incorrect. Rather than giving the object to remove, you give the index of the object to remove, defaulting to the last item of the list if no argument is given. So the row should read as:

list.pop(index=-1) -- removes and returns object at given or last index from list

186 :: 6.14.1 : Example 6.2 : call to showmenu() on line 47 should be indented.

193 :: 6.14.2 : final sentence should refer to Section 13.16 rather than 13.18.

193 :: 6.15 : first sentence in "How to Create and Assign Tuples" section should start as "Creating and assigning tuples..." not lists.

194 :: 6.15 : first line of interactive code should read:
>>> aTuple[1:4]

194 :: 6.15 : final sentence should refer to removing an entire "tuple," not list, keeping in mind again, that most of the time, programmers will just let an object go out-of-scope rather than explicitly deleting an object.

201 :: 6.18 : description of UserList module should refer to Section 13.16 rather than 13.18

209 :: 6.20 : Exercise 6-9 : 1st sentence should refer to Exercise 5-13, not 6-13

Chapter 7

Chapter 8

244 :: 8.5.4 : In the for-loop at the bottom of the page, the C variable i is misspelled and should be eachVal: for (eachVal = 2; eachVal < 19; eachVal += 3) {...

252 :: 8.10 : Exercise 8-9 : The actual problem does not follow the description of Fibonacci numbers. The rest should read: Write a routine such that given N, display the value of the N^th Fibonacci number. For example, the first Fibonacci number is 1, the 6th is 8, and so on.

Chapter 9

267 :: 9.5 : In the paragraph for sys.stdout.write() near the middle of the page, the 2nd sentence should read that "readline() executed on sys.stdin preserves the NEWLINE..." and not "readline."

268 :: 9.5 : The 2nd sentence at the top of the page should read: 'The names "argc" and "argv"....'

275 :: 9.7 : The pseudocode in the 2nd section is missing one line with a call to os.chdir():

>>> os.mkdir('example')
>>> os.chdir('example')
>>> cwd
   :

Also, the exception with os.listdir() is intentional, to show you the error which results when no directory name is given to the function.

276 :: 9.7 : The pseudocode in the 2nd section is missing the assignment of the allLines variable:

>>> file = open(path)
>>> allLines = file.readlines()
>>> file.close()
   :

Chapter 10

315 :: 10.6.1 : first sentence of 2nd to last paragraph should italicize without any parameters.

320 :: 10.8 :: Table 10.2 : TableError should be TabError

Chapter 11

350 :: 11.6.2 : print statement displaying 1st formal argument in dictVarArgs() function should read as:

print 'format arg1:', arg1

... and not ...

print 'format arg1:', dictVarArgs

350 :: 11.6.2 : in example execution of dictVarArgs(), 2nd invocation should set arg1 not a to 'mystery'

353 (top) :: 11.6.3 : add final new sentence before Section 11.7: Prior to 1.6, variable objects could only be passed to to apply() with the function object for invocation.

362 :: 11.7.2 (filter()) : pseudocode is improperly indented... the code should look like:

def filter(bool_func, sequence):
    filtered_seq = []
    for eachItem in sequence:
	if apply(bool_func, (eachItem,)):
	    filtered_seq.append(eachItem)
    return filtered_seq

363 :: 11.7.2 (filter()) : first round code for oddnogen.py is also indented improperly... it should appear as:

from random import randint

def odd(n):
    return n % 2

def main():
    allNums = []
    for eachNum in range(10):
	allNums.append(randint(1, 101))
    oddNums = filter(odd, allNums)
    print len(oddNums), oddNums

if __name__ == '__main__':
    main()

367 :: 11.7.2 (map()) : change the reference of "Zip()" to zip() (font should also be Courier in another reference on the bottom of p. 369).

372 :: 11.7.2 (reduce()) : mathematical operation for the example is missing 2 left parentheses: ((((0 + 1) + 2) + 3) + 4) => 10.

Chapter 12

Chapter 13

441 :: 13.10.2 (Core Note) : output of instanantiation is incorrect... it should be:

>>> c = C()
calling C's constructor

449 :: 13.12 : section title should be "Types vs. Classes/Instances"

454 :: 13.13.1 : output of last interactive example should not be indented:

>>> print myPair
(-5, 9)

463 (top) :: 13.13.2 : first paragraph is for Lines 42-54

Chapter 14

Chapter 15

Chapter 16

Chapter 17

Chapter 18

Chapter 19

664 :: 19.5.1 : "CN" Core Note logo should be "CT", meaning a Core Tip logo.

682 :: 19.5.1 : Example 19.6 : The first two words of the description of this code should read, "This script..." rather than "The crawler...".

684 :: 19.5.1 : Example 19.6 : or on line 108 of advcgi.py should be for. (The source code is correct though.)

690-691 :: 19.7.1 : output from the myhttpd.py webserver wraps... lines of output should be on single lines.

Chapter 20

BackMatter

Code

Chapter 14

Chapter 16