David Beazley and Brian K. Jones
T
H
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R
D
E
D
ITI
O
N
Python
C ookbook
Py thon
Cookbook,
Thi
r
d
Edition
by David Beazley and Brian K. Jones
Copyright © 2013 David Beazley and Brian Jones. All rights reserved.
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[LSI]
Table
of
Contents
P
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xi
1.
D
ata
S
t
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uctu
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es
and
Algo
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1
1.1. U
n
packing a Sequence into Separate Variables 1
1.2. Unpacking Elements from Iterables of Arbitrary Length 3
1.3. Keeping the Last N Items 5
1.4. Finding the Largest or Smallest N Items 7
1.5. Implementing a Priority Queue 8
1.6. Mapping Keys to Multiple Values in a Dictionary 11
1.7. Keeping Dictionaries in Order 12
1.8. Calculating with Dictionaries 13
1.9. Finding Commonalities in Two Dictionaries 15
1.10. Removing Duplicates from a Sequence while Maintaining Order 17
1.11. Naming a Slice 18
1.12. Determining the Most Frequently Occurring Items in a Sequence 20
1.13. Sorting a List of Dictionaries by a Common Key 21
1.14. Sorting Objects Without Native Comparison Support 23
1.15. Grouping Records Together Based on a Field 24
1.16. Filtering Sequence Elements 26
1.17. Extracting a Subset of a Dictionary 28
1.18. Mapping Names to Sequence Elements 29
1.19. Transforming and Reducing Data at the Same Time 32
1.20. Combining Multiple Mappings into a Single Mapping 33
2.
S
t
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ings
and
Text.
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37
2.1. Splitting Strings on Any of M
ultiple Delimiters 37
2.2. Matching Text at the Start or End of a String 38
2.3. Matching Strings Using Shell Wildcard Patterns 40
2.4. Matching and Searching for Text Patterns 42
iii
