Synopses & Reviews
Portable, powerful, and a breeze to use, Python is the popular open source object-oriented programming language used for both standalone programs and scripting applications. It is now being used by an increasing number of major organizations, including NASA and Google.Updated for Python 2.4, The Python Cookbook, 2nd Edition offers a wealth of useful code for all Python programmers, not just advanced practitioners. Like its predecessor, the new edition provides solutions to problems that Python programmers face everyday.It now includes over 200 recipes that range from simple tasks, such as working with dictionaries and list comprehensions, to complex tasks, such as monitoring a network and building a templating system. This revised version also includes new chapters on topics such as time, money, and metaprogramming.Here's a list of additional topics covered:
- Manipulating text
- Searching and sorting
- Working with files and the filesystem
- Object-oriented programming
- Dealing with threads and processes
- System administration
- Interacting with databases
- Creating user interfaces
- Network and web programming
- Processing XML
- Distributed programming
- Debugging and testing
Another advantage of The Python Cookbook
, 2nd Edition is its trio of authors--three well-known Python programming experts, who are highly visible on email lists and in newsgroups, and speak often at Python conferences.With scores of practical examples and pertinent background information, The Python Cookbook
, 2nd Edition is the one source you need if you're looking to build efficient, flexible, scalable, and well-integrated systems.
New edition has additional chapters and over 200 new recipes, updated for Python 2.4
About the Author
Alex Martelli spent 8 years with IBM Research, winning three Outstanding Technical Achievement Awards. He then spent 13 as a Senior Software Consultant at think3 inc, developing libraries, network protocols, GUI engines, event frameworks, and web access frontends. He has also taught programming languages, development methods, and numerical computing at Ferrara University and other venues. He's a C++ MVP for Brainbench, and a member of the Python Software Foundation. He currently works for AB Strakt, a Python-centered software house in G teborg, Sweden, mostly by telecommuting from his home in Bologna, Italy. Alex's proudest achievement is the articles that appeared in Bridge World (January/February 2000), which were hailed as giant steps towards solving issues that had haunted contract bridge theoreticians for decades.
Anna Martelli Ravenscroft has a background in training and mentoring, particularly in office technologies. She brings a fresh perspective to Python with a focus on practical, real-world problem solving. Anna is currently pursuing a degree at Stanford University and often pair programs (in Python) with her husband and children.
David Ascher is the lead for Python projects at ActiveState, including Komodo, ActiveState's integrated development environment written mostly in Python. David has taught courses about Python to corporations, in universities, and at conferences. He also organized the Python track at the 1999 and 2000 O'Reilly Open Source Conventions, and was the program chair for the 10th International Python Conference. In addition, he co-wrote Learning Python (both editions) and serves as a director of the Python Software Foundation. David holds a B.S. in physics and a Ph.D. in cognitive science, both from Brown University.
Table of Contents
Preface; The Design of the Book; The Implementation of the Book; Using the Code from This Book; Audience; Organization; Further Reading; Conventions Used in This Book; How to Contact Us; Safari® Enabled; Acknowledgments; Chapter 1: Text; 1.1 Introduction; 1.1 Processing a String One Character at a Time; 1.2 Converting Between Characters and Numeric Codes; 1.3 Testing Whether an Object Is String-like; 1.4 Aligning Strings; 1.5 Trimming Space from the Ends of a String; 1.6 Combining Strings; 1.7 Reversing a String by Words or Characters; 1.8 Checking Whether a String Contains a Set of Characters; 1.9 Simplifying Usage of Strings' translate Method; 1.10 Filtering a String for a Set of Characters; 1.11 Checking Whether a String Is Text or Binary; 1.12 Controlling Case; 1.13 Accessing Substrings; 1.14 Changing the Indentation of a Multiline String; 1.15 Expanding and Compressing Tabs; 1.16 Interpolating Variables in a String; 1.17 Interpolating Variables in a Stringin Python 2.4; 1.18 Replacing Multiple Patterns in a Single Pass; 1.19 Checking a String for Any of Multiple Endings; 1.20 Handling International Text with Unicode; 1.21 Converting Between Unicode and Plain Strings; 1.22 Printing Unicode Charactersto Standard Output; 1.23 Encoding Unicode Data for XML and HTML; 1.24 Making Some Strings Case-Insensitive; 1.25 Converting HTML Documents to Texton a Unix Terminal; Chapter 2: Files; 2.1 Introduction; 2.1 Reading from a File; 2.2 Writing to a File; 2.3 Searching and Replacing Text in a File; 2.4 Reading a Specific Line from a File; 2.5 Counting Lines in a File; 2.6 Processing Every Word in a File; 2.7 Using Random-Access Input/Output; 2.8 Updating a Random-Access File; 2.9 Reading Data from zip Files; 2.10 Handling a zip File Inside a String; 2.11 Archiving a Tree of Files into a Compressed tar File; 2.12 Sending Binary Data to Standard Output Under Windows; 2.13 Using a C++-like iostream Syntax; 2.14 Rewinding an Input File to the Beginning; 2.15 Adapting a File-like Object to a True File Object; 2.16 Walking Directory Trees; 2.17 Swapping One File Extension for Another Throughout a Directory Tree; 2.18 Finding a File Given a Search Path; 2.19 Finding Files Given a Search Path and a Pattern; 2.20 Finding a File on the Python Search Path; 2.21 Dynamically Changing the PythonSearch Path; 2.22 Computing the Relative Path from One Directory to Another; 2.23 Reading an Unbuffered Character in a Cross-Platform Way; 2.24 Counting Pages of PDF Documents on Mac OS X; 2.25 Changing File Attributes on Windows; 2.26 Extracting Text from OpenOffice.org Documents; 2.27 Extracting Text from Microsoft Word Documents; 2.28 File Locking Using a Cross-Platform API; 2.29 Versioning Filenames; 2.30 Calculating CRC-64 Cyclic Redundancy Checks; Chapter 3: Time and Money; 3.1 Introduction; 3.1 Calculating Yesterday and Tomorrow; 3.2 Finding Last Friday; 3.3 Calculating Time Periods in a Date Range; 3.4 Summing Durations of Songs; 3.5 Calculating the Number of Weekdays Between Two Dates; 3.6 Looking up Holidays Automatically; 3.7 Fuzzy Parsing of Dates; 3.8 Checking Whether Daylight Saving Time Is Currently in Effect; 3.9 Converting Time Zones; 3.10 Running a Command Repeatedly; 3.11 Scheduling Commands; 3.12 Doing Decimal Arithmetic; 3.13 Formatting Decimals as Currency; 3.14 Using Python as a Simple Adding Machine; 3.15 Checking a Credit Card Checksum; 3.16 Watching Foreign Exchange Rates; Chapter 4: Python Shortcuts; 4.1 Introduction; 4.1 Copying an Object; 4.2 Constructing Lists with List Comprehensions; 4.3 Returning an Element of a List If It Exists; 4.4 Looping over Items and Their Indices in a Sequence; 4.5 Creating Lists of Lists Without Sharing References; 4.6 Flattening a Nested Sequence; 4.7 Removing or Reordering Columnsin a List of Rows; 4.8 Transposing Two-Dimensional Arrays; 4.9 Getting a Value from a Dictionary; 4.10 Adding an Entry to a Dictionary; 4.11 Building a Dictionary Without Excessive Quoting; 4.12 Building a Dict from a List of Alternating Keys and Values; 4.13 Extracting a Subset of a Dictionary; 4.14 Inverting a Dictionary; 4.15 Associating Multiple Values with Each Key in a Dictionary; 4.16 Using a Dictionary to Dispatch Methods or Functions; 4.17 Finding Unions and Intersections of Dictionaries; 4.18 Collecting a Bunch of Named Items; 4.19 Assigning and Testing with One Statement; 4.20 Using printf in Python; 4.21 Randomly Picking Items with Given Probabilities; 4.22 Handling Exceptions Within an Expression; 4.23 Ensuring a Name Is Defined in a Given Module; Chapter 5: Searching and Sorting; 5.1 Introduction; 5.1 Sorting a Dictionary; 5.2 Sorting a List of Strings Case-Insensitively; 5.3 Sorting a List of Objects by an Attribute of the Objects; 5.4 Sorting Keys or Indices Basedon the Corresponding Values; 5.5 Sorting Strings with Embedded Numbers; 5.6 Processing All of a List's Items in Random Order; 5.7 Keeping a Sequence Ordered as Items Are Added; 5.8 Getting the First Few Smallest Items of a Sequence; 5.9 Looking for Items in a Sorted Sequence; 5.10 Selecting the nth Smallest Element of a Sequence; 5.11 Showing off quicksort in Three Lines; 5.12 Performing Frequent Membership Tests on a Sequence; 5.13 Finding Subsequences; 5.14 Enriching the Dictionary Type with Ratings Functionality; 5.15 Sorting Names and Separating Them by Initials; Chapter 6: Object-Oriented Programming; 6.1 Introduction; 6.1 Converting Among Temperature Scales; 6.2 Defining Constants; 6.3 Restricting Attribute Setting; 6.4 Chaining Dictionary Lookups; 6.5 Delegating Automatically as an Alternative to Inheritance; 6.6 Delegating Special Methods in Proxies; 6.7 Implementing Tuples with Named Items; 6.8 Avoiding Boilerplate Accessors for Properties; 6.9 Making a Fast Copy of an Object; 6.10 Keeping References to Bound Methods Without Inhibiting Garbage Collection; 6.11 Implementing a Ring Buffer; 6.12 Checking an Instance for Any State Changes; 6.13 Checking Whether an Object Has Necessary Attributes; 6.14 Implementing the State Design Pattern; 6.15 Implementing the "Singleton" Design Pattern; 6.16 Avoiding the "Singleton" Design Pattern with the Borg Idiom; 6.17 Implementing the Null Object Design Pattern; 6.18 Automatically Initializing Instance Variables from _ _init_ _ Arguments; 6.19 Calling a Superclass _ _init_ _ Method If It Exists; 6.20 Using Cooperative Supercalls Concisely and Safely; Chapter 7: Persistence and Databases; 7.1 Introduction; 7.1 Serializing Data Using the marshal Module; 7.2 Serializing Data Using the pickle and cPickle Modules; 7.3 Using Compression with Pickling; 7.4 Using the cPickle Module on Classes and Instances; 7.5 Holding Bound Methods in a Picklable Way; 7.6 Pickling Code Objects; 7.7 Mutating Objects with shelve; 7.8 Using the Berkeley DB Database; 7.9 Accessing a MySQL Database; 7.10 Storing a BLOB in a MySQL Database; 7.11 Storing a BLOB in a PostgreSQL Database; 7.12 Storing a BLOB in a SQLite Database; 7.13 Generating a Dictionary Mapping Field Names to Column Numbers; 7.14 Using dtuple for Flexible Accessto Query Results; 7.15 Pretty-Printing the Contents of Database Cursors; 7.16 Using a Single Parameter-Passing Style Across Various DB API Modules; 7.17 Using Microsoft Jet via ADO; 7.18 Accessing a JDBC Database from a Jython Servlet; 7.19 Using ODBC to Get Excel Data with Jython; Chapter 8: Debugging and Testing; 8.1 Introduction; 8.1 Disabling Execution of Some Conditionals and Loops; 8.2 Measuring Memory Usage on Linux; 8.3 Debugging the Garbage-Collection Process; 8.4 Trapping and Recording Exceptions; 8.5 Tracing Expressions and Comments in Debug Mode; 8.6 Getting More Information from Tracebacks; 8.7 Starting the Debugger Automatically After an Uncaught Exception; 8.8 Running Unit Tests Most Simply; 8.9 Running Unit Tests Automatically; 8.10 Using doctest with unittest in Python 2.4; 8.11 Checking Values Against Intervals in Unit Testing; Chapter 9: Processes, Threads, and Synchronization; 9.1 Introduction; 9.1 Synchronizing All Methods in an Object; 9.2 Terminating a Thread; 9.3 Using a Queue.Queue as a Priority Queue; 9.4 Working with a Thread Pool; 9.5 Executing a Function in Parallel on Multiple Argument Sets; 9.6 Coordinating Threads by Simple Message Passing; 9.7 Storing Per-Thread Information; 9.8 Multitasking Cooperatively Without Threads; 9.9 Determining Whether Another Instanceof a Script Is Already Running in Windows; 9.10 Processing Windows Messages Using MsgWaitForMultipleObjects; 9.11 Driving an External Process with popen; 9.12 Capturing the Output and Error Streams from a Unix Shell Command; 9.13 Forking a Daemon Process on Unix; Chapter 10: System Administration; 10.1 Introduction; 10.1 Generating Random Passwords; 10.2 Generating Easily Remembered Somewhat-Random Passwords; 10.3 Authenticating Users by Means of a POP Server; 10.4 Calculating Apache Hits per IP Address; 10.5 Calculating the Rate of Client Cache Hits on Apache; 10.6 Spawning an Editor from a Script; 10.7 Backing Up Files; 10.8 Selectively Copying a Mailbox File; 10.9 Building a Whitelist of Email Addresses From a Mailbox; 10.10 Blocking Duplicate Mails; 10.11 Checking Your Windows Sound System; 10.12 Registering or Unregistering a DLL on Windows; 10.13 Checking and Modifying the Set of Tasks Windows Automatically Runs at Login; 10.14 Creating a Share on Windows; 10.15 Connecting to an Already Running Instance of Internet Explorer; 10.16 Reading Microsoft Outlook Contacts; 10.17 Gathering Detailed System Informationon Mac OS X; Chapter 11: User Interfaces; 11.1 Introduction; 11.1 Showing a Progress Indicator on a Text Console; 11.2 Avoiding lambda in Writing Callback Functions; 11.3 Using Default Values and Bounds with tkSimpleDialog Functions; 11.4 Adding Drag and Drop Reordering to a Tkinter Listbox; 11.5 Entering Accented Characters in Tkinter Widgets; 11.6 Embedding Inline GIFs Using Tkinter; 11.7 Converting Among Image Formats; 11.8 Implementing a Stopwatch in Tkinter; 11.9 Combining GUIs and Asynchronous I/Owith Threads; 11.10 Using IDLE's Tree Widget in Tkinter; 11.11 Supporting Multiple Values per Row in a Tkinter Listbox; 11.12 Copying Geometry Methods and Options Between Tkinter Widgets; 11.13 Implementing a Tabbed Notebook for Tkinter; 11.14 Using a wxPython Notebook with Panels; 11.15 Implementing an ImageJ Plug-in in Jython; 11.16 Viewing an Image from a URL with Swing and Jython; 11.17 Getting User Input on Mac OS; 11.18 Building a Python Cocoa GUI Programmatically; 11.19 Implementing Fade-in Windows with IronPython; Chapter 12: Processing XML; 12.1 Introduction; 12.1 Checking XML Well-Formedness; 12.2 Counting Tags in a Document; 12.3 Extracting Text from an XML Document; 12.4 Autodetecting XML Encoding; 12.5 Converting an XML Document into a Tree of Python Objects; 12.6 Removing Whitespace-only Text Nodes from an XML DOM Node's Subtree; 12.7 Parsing Microsoft Excel's XML; 12.8 Validating XML Documents; 12.9 Filtering Elements and Attributes Belonging to a Given Namespace; 12.10 Merging Continuous Text Events with a SAX Filter; 12.11 Using MSHTML to Parse XML or HTML; Chapter 13: Network Programming; 13.1 Introduction; 13.1 Passing Messages with Socket Datagrams; 13.2 Grabbing a Document from the Web; 13.3 Filtering a List of FTP Sites; 13.4 Getting Time from a Server via the SNTP Protocol; 13.5 Sending HTML Mail; 13.6 Bundling Files in a MIME Message; 13.7 Unpacking a Multipart MIME Message; 13.8 Removing Attachments from an Email Message; 13.9 Fixing Messages Parsed by Python 2.4 email.FeedParser; 13.10 Inspecting a POP3 Mailbox Interactively; 13.11 Detecting Inactive Computers; 13.12 Monitoring a Network with HTTP; 13.13 Forwarding and Redirecting Network Ports; 13.14 Tunneling SSL Through a Proxy; 13.15 Implementing the Dynamic IP Protocol; 13.16 Connecting to IRC and Logging Messages to Disk; 13.17 Accessing LDAP Servers; Chapter 14: Web Programming; 14.1 Introduction; 14.1 Testing Whether CGI Is Working; 14.2 Handling URLs Within a CGI Script; 14.3 Uploading Files with CGI; 14.4 Checking for a Web Page's Existence; 14.5 Checking Content Type via HTTP; 14.6 Resuming the HTTP Download of a File; 14.7 Handling Cookies While Fetching Web Pages; 14.8 Authenticating with a Proxy for HTTPS Navigation; 14.9 Running a Servlet with Jython; 14.10 Finding an Internet Explorer Cookie; 14.11 Generating OPML Files; 14.12 Aggregating RSS Feeds; 14.13 Turning Data into Web Pages Through Templates; 14.14 Rendering Arbitrary Objects with Nevow; Chapter 15: Distributed Programming; 15.1 Introduction; 15.1 Making an XML-RPC Method Call; 15.2 Serving XML-RPC Requests; 15.3 Using XML-RPC with Medusa; 15.4 Enabling an XML-RPC Server to Be Terminated Remotely; 15.5 Implementing SimpleXMLRPCServer Niceties; 15.6 Giving an XML-RPC Server a wxPython GUI; 15.7 Using Twisted Perspective Broker; 15.8 Implementing a CORBA Server and Client; 15.9 Performing Remote Logins Using telnetlib; 15.10 Performing Remote Logins with SSH; 15.11 Authenticating an SSL Client over HTTPS; Chapter 16: Programs About Programs; 16.1 Introduction; 16.1 Verifying Whether a String Represents a Valid Number; 16.2 Importing a Dynamically Generated Module; 16.3 Importing from a Module Whose Name Is Determined at Runtime; 16.4 Associating Parameters with a Function (Currying); 16.5 Composing Functions; 16.6 Colorizing Python Source Using the Built-in Tokenizer; 16.7 Merging and Splitting Tokens; 16.8 Checking Whether a String Has Balanced Parentheses; 16.9 Simulating Enumerations in Python; 16.10 Referring to a List Comprehension While Building It; 16.11 Automating the py2exe Compilation of Scripts into Windows Executables; 16.12 Binding Main Script and Modules into One Executable on Unix; Chapter 17: Extending and Embedding; 17.1 Introduction; 17.1 Implementing a Simple Extension Type; 17.2 Implementing a Simple Extension Type with Pyrex; 17.3 Exposing a C++ Library to Python; 17.4 Calling Functions from a Windows DLL; 17.5 Using SWIG-Generated Modules in a Multithreaded Environment; 17.6 Translating a Python Sequence into a C Array with the PySequence_Fast Protocol; 17.7 Accessing a Python Sequence Item-by-Item with the Iterator Protocol; 17.8 Returning None from a Python-Callable C Function; 17.9 Debugging Dynamically Loaded C Extensions with gdb; 17.10 Debugging Memory Problems; Chapter 18: Algorithms; 18.1 Introduction; 18.1 Removing Duplicates from a Sequence; 18.2 Removing Duplicates from a Sequence While Maintaining Sequence Order; 18.3 Generating Random Samples with Replacement; 18.4 Generating Random Samples Without Replacement; 18.5 Memoizing (Caching) the Return Values of Functions; 18.6 Implementing a FIFO Container; 18.7 Caching Objects with a FIFO Pruning Strategy; 18.8 Implementing a Bag (Multiset) Collection Type; 18.9 Simulating the Ternary Operator in Python; 18.10 Computing Prime Numbers; 18.11 Formatting Integers as Binary Strings; 18.12 Formatting Integers as Strings in Arbitrary Bases; 18.13 Converting Numbers to Rationals via Farey Fractions; 18.14 Doing Arithmetic with Error Propagation; 18.15 Summing Numbers with Maximal Accuracy; 18.16 Simulating Floating Point; 18.17 Computing the Convex Hulls and Diameters of 2D Point Sets; Chapter 19: Iterators and Generators; 19.1 Introduction; 19.1 Writing a range-like Function with Float Increments; 19.2 Building a List from Any Iterable; 19.3 Generating the Fibonacci Sequence; 19.4 Unpacking a Few Items in a Multiple Assignment; 19.5 Automatically Unpacking the Needed Number of Items; 19.6 Dividing an Iterable into n Slices of Stride n; 19.7 Looping on a Sequence by Overlapping Windows; 19.8 Looping Through Multiple Iterables in Parallel; 19.9 Looping Through the Cross-Product of Multiple Iterables; 19.10 Reading a Text File by Paragraphs; 19.11 Reading Lines with Continuation Characters; 19.12 Iterating on a Stream of Data Blocks as a Stream of Lines; 19.13 Fetching Large Record Sets from a Database with a Generator; 19.14 Merging Sorted Sequences; 19.15 Generating Permutations, Combinations, and Selections; 19.16 Generating the Partitions of an Integer; 19.17 Duplicating an Iterator; 19.18 Looking Ahead into an Iterator; 19.19 Simplifying Queue-Consumer Threads; 19.20 Running an Iterator in Another Thread; 19.21 Computing a Summary Report with itertools.groupby; Chapter 20: Descriptors, Decorators,and Metaclasses; 20.1 Introduction; 20.1 Getting Fresh Default Values at Each Function Call; 20.2 Coding Properties as Nested Functions; 20.3 Aliasing Attribute Values; 20.4 Caching Attribute Values; 20.5 Using One Method as Accessorfor Multiple Attributes; 20.6 Adding Functionality to a Class by Wrapping a Method; 20.7 Adding Functionality to a Class by Enriching All Methods; 20.8 Adding a Method to a Class Instance at Runtime; 20.9 Checking Whether Interfaces Are Implemented; 20.10 Using _ _new_ _ and _ _init_ _ Appropriately in Custom Metaclasses; 20.11 Allowing Chaining of Mutating List Methods; 20.12 Using Cooperative Super calls with Terser Syntax; 20.13 Initializing Instance Attributes Without Using _ _init_ _; 20.14 Automatic Initialization of Instance Attributes; 20.15 Upgrading Class Instances Automatically on reload; 20.16 Binding Constants at Compile Time; 20.17 Solving Metaclass Conflicts; Colophon;