Expert Python Programming

Errata type: Typo | Page number: 13

"tar -xzvf" duplicated in last line.
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Errata type: Typo | Page number: 16

"Installing MSYS", the URL is the same as the one from "Installing MinGW" on page 15:
http://sourceforge.net/project/showfiles.php?group_id=2435&package_id=240780
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Errata type: Typo | Page number: 28

The following sentence at the end of the 'Extra Binaries' section is incorrect.
Notice that both grep Under Windows, these are available with MSYS.
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Errata type: Technical | Page number: 34

In the while loop of that example:
Change: "if i % 2 == 0" to "if i % 2 == 0 and i != 4"
And in the next snippet:
Change: [i for i in range(10) if i % 2 == 0] to [i for i in range(10) if i % 2 == 0 and i != 4]
and Both [0, 2, 4, 6, 8] should be replaced by [0, 2, 6, 8]
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Errata type: Typo | Page number: 39

Missing quotation mark to mark the end of the string "Don't ask yourself" in line 7 of the psycologist function.
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Errata type: Technical | Page number: 41

import time
This import is unnecessary. Remove it
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Errata type: Technical | Page number: 45

In last line: "1g1e1t1 8u1p" should be replaced by "1g1e1t1 18u1p".
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Errata type: Technical | Page number: 45

Replace: import itertools def with_head(iterable, headsize=1):...
a, b = itertools.tee(iterable)...
return list(itertools.islice(a, headsize)), b
with_head(seq)([1], itertools.tee object at 0x100c698) with_head(seq, 4)([1, 2, 3, 4], itertools.tee object at 0x100c670
With:
import itertools seq = range(10) def with_head(iterable, headsize=1):...
a, b = itertools.tee(iterable)...
return list(itertools.islice(a, headsize)), b...
with_head(seq)([0], itertools.tee object at with_head(seq, 4)([0, 1, 2, 3], itertools.tee object at 0x8a698)
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Errata type: Typo | Page number: 50

The variable called rpc_info in page is called rpc_infos in page 51.

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Errata type: Typo | Page number: 55

@locker
...def thread_safe():
...pass...
this should be:
@synchronized&
... def thread_safe():
... pass
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Errata type: Typo | Page number: 58

there is a grammar mistake at the end of the first textual paragraph:"... it does not returning anything."
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Errata type: Typo | Page number: 59

"import logging" is unnecessary in context example.
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Errata type: Typo | Page number: 60

After the word "example" and prior to the comma, there is an space.
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Errata type: Technical | Page number: 64

The traceback :
"ValueError: This value already exists for 'value'"
Should be:
"DistinctError: This value already exists for 'value'"
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Errata type: Typo | Page number: 69

"The tail is the first element of a list and head contains rest of the elements.
This should be:
"The head is the first element of a list and tail contains the rest of the elements."
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Replace:
# 1- looking for definition
if hasattr(MyClass, attribute):
attribute = MyClass.attribute
AttributeClass = attribute.__class__
# 2 - does attribute definition has a setter
if hasattr(AttributeClass, __set__):
# lets use it
AttributeClass.__set__(attribute, instance,value)
# 3 - regular way
instance.__dict__[attribute] = value
# or 'attribute' is not found in __dict__writable = (hasattr(AttributeClass, '__set__') or 'attribute' not in instance.__dict__) if readable and writable:
# 4 let's call the descriptor
return AttributeClass.__get__(attribute,instance, MyClass)
# 5 - regular access with __dict__return instance.__dict__['attribute']
# 1. looking for definition
if hasattr(MyClass, 'attribute'):
attribute = MyClass.attributeAttributeClass = attribute.__class__
# 2. found a getter, using it
if hasattr(AttributeClass, '__get__':
return AttributeClass.__get__(attribute, instance, MyClass)
# 3 - regular access with __dict__
return instance.__dict__['attribute']
Also:
replace "when a class attribute is defined and has a getter and a setter method"
by "when a class attribute is defined and has a getter method"
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Errata type: Technical | Page number: 76

replace:
instance.__dict__ = {}
instance_of.__dict__{}
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Errata type: Technical | Page number: 76

The use of MyDescriptor in the code around the center of the table is wrong and should be changed to UpperString (the name of the descriptor actually defined earlier in the code)
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Errata type: Technical | Page number: 76

MyClass.new_att = MyDescriptor()
should be replaced by
MyClass.new_att = UpperString()
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Errata type: Technical | Page number: 105

Usage of a variable called "args" which does not exist in the method "sum(sequence)"
replace "args" by "sequence".

Errata type: Technical | Page number: 108

In the call to execute, context should presumably be passed as a second argument (it's currently being ignored).
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Errata type: Typo | Page number: 111

The correct contents should be "it is more than 500 lines" where that has been substituted by than.
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Errata type: Typo | Page number: 114

text in the 3rd paragraph mentions .pylinrc -- shd be .pylintrc instead
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Errata type: Typo | Page number: 121

in the para after the bulleted list, at the end, "it was build on." should be "it was built on."
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Errata type: Typo | Page number: 137

Instead of "pbp.skeles" it should be "pbp.skels" to use the same name in the code example.
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Errata type: Typo | Page number: 192

The picture of the browser is for "http://localhost:8000/?style=gitweb", not the "http://localhost:8000" suggested in in the top line of the page.
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Errata type: Technical | Page number: 222

change :
$ hg clone
by :
$ hg clone . ../release-atomisator-0.1.0
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Errata type: Technical | Page number: 258

suite is redefined in test_suite() and that causes an error. TestCases and TestSuites must be instantiated before passing them to addTest(). Here is the modified code:
def test_suite():
"""builds the test suite."""
def _suite(test_class):
return unittest.makeSuite(test_class)
suite = unittest.TestSuite()
suite.addTests((_suite(MyTests), _suite(MyTests2)))
return suite
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Errata type: Technical | Page number: 289

change:
"all local references in a function are removed after the interpreter:- leaves the function- makes sure the object is not being used anymore"
with :
"all local references in a function are removed after the interpreter leaves the function. If there's no more remaining reference to the object, it is removed from the memory as well."
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Errata type: Typo | Page number: 300

Broken link:
http://pages.cs.wisc.edu/~hasti/cs367-common/notes/COMPLEXITY.html#bigO
Should be:
http://pages.cs.wisc.edu/~hasti/cs367-common/notes/4.COMPLEXITY.html#bigO
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Errata type: Typo | Page number: 342

the URL for Behrens' pattern should end with .../8747 and *NOT* with /8747V
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