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(Obsolete). This (highly incomplete) module contains a parser for timezone specifications. When you import this module, it parses the content of the TZ environment variable. Example: Using the tzparse module # File: import os if not os.environ.has_key(“TZ”): # set it to something… os.environ[“TZ”] = “EST+5EDT;100/2,300/2” # importing this module will parse the TZ variable import […]

(New in 2.0). This module reads robots.txt files, which are used to implement the Robot Parsing. If you’re implementing an HTTP robot that will visit arbitrary sites on the net (not just your own sites), it’s a good idea to use this module to check that you really are $ python robotparser-example-1.py may fetch the home page

The TidyHTMLTreeBuilder parser can read (almost) arbitrary HTML files, and turn them into well-formed element trees. This parser uses a library version of Dave Raggett’s HTML Tidy utility to fix any problems with the HTML before converting it to XHTML (the XML version of HTML). Note: If you don’t want to (or cannot) install binary Python extensions, you can use the TidyTools module

The ElementSoup module is a (slightly experimental) wrapper for Leonard Richardson’s robust BeautifulSoup HTML parser, which turns the BeautifulSoup data structure into an element tree. The resulting combo is similar to ElementTidy, but a lot less picky. And therefore, a lot more practical. Which is good. Code (latest versions): Just grab the files and put them in your project directory,

To update the text displayed on a button in Tkinter, you can use the config() method or the configure() method to modify the button’s text attribute. Here’s an example: import tkinter as tk def update_text(): button.config(text=”New Text”) # Update the button text root = tk.Tk() button = tk.Button(root, text=”Old Text”) button.pack() update_button = tk.Button(root, text=”Update

The function of a Tkinter bubble shooter game typically involves the creation of an interactive game interface using the Tkinter library in Python. Below are several essential features and functions that can be implemented in such a game: Game Board: Construct a game board utilizing a canvas widget that visually represents bubbles and their respective

The xmllib module This module provides a simple XML parser, using regular expressions to pull the XML data apart. The parser does basic checks on the document, such as checking that there is only one top-level element, and checking that all tags are balanced. You feed XML data to this parser piece by piece (as

Overview This chapter describes a number of modules that are used to parse different file formats. Markup Languages Python comes with extensive support for the Extensible Markup Language XML and Hypertext Markup Language (HTML) file formats. Python also provides basic support for Standard Generalized Markup Language (SGML). All these formats share the same basic structure (this isn’t so strange, since both

You’ve been working on a complex Python script, investing hours of effort and dedication to ensure its smooth execution. You’ve accounted for every possible scenario and exception, meticulously crafting your code. However, there’s one often-overlooked aspect: the graceful exit. When your script completes its task or encounters an unexpected error, how can you ensure that

This module implements a simple helper class, HTTPClient, which can send an XML document (represented either as an element tree or a string) to a remote server, and parse the result into an element tree. A Simple XML-Over-HTTP Helper (File: HTTPClient.py) The main workhorse is the do_request method, which uses the httplib library module for all protocol-related stuff. The HTTP class represents a connection to

The Label widget is a standard Tkinter widget used to display a text or image on the screen. The label can only display text in a single font, but the text may span more than one line. In addition, one of the characters can be underlined, for example to mark a keyboard shortcut. When to use the

(New in 2.2) Tools for manipulation of all sorts of email messages. The email package replaces simpler modules, such as rfc822 and mimetools, with a much more flexible message object, and associated parsers. Parsing Messages  The easiest way to parse messages is to use the message_from_file or message_from_string helpers in the email toplevel module. The former takes a file handle, the latter a string object: Parsing

I just added support for a new “pixel access” method to PIL 1.1.6. The load method now returns a pixel access object, which behaves like a 2-dimensional mapping. You can use the access object on both sides of an assignment statement; as an expression, it fetches the given pixel value, and as an assignment target, it updates

The SQLITE database has limited support for large binary objects (BLOBS). There’s a limitation of 1 megabyte for each row of data, and the database uses NUL bytes to separate columns in the storage. Note: This limitation has been removed in SQLITE 3.0. For best operation in large tables, the SQLITE author recommends keeping the row size around

__future__ A registry of features supported by the from __future__ compiler directive.difflib Tools to detect differences and calculate deltas between lists of objects.distutils (package) Tools to distribute and install Python extensions.doctest A test framework, based on docstrings. To use this for general testing, you can write test scripts and use doctest to make sure the test scripts work as

The Tkinter BitmapImage Class The BitmapImage class provides a simple image class, for monochrome (two-color) images. When to use the BitmapImage Class This class can be used to display bitmap images in labels, buttons, canvases, and text widgets. The bitmap loader reads X11 bitmap files. To use other formats, use the PhotoImage class. Patterns An X11 bitmap image consists of

A Python Code Generator A common complaint about Python’s syntax is that it’s impossible to generate Python code on the fly, from a program. Here’s a simple helper class that helps you do exactly that: # # a Python code generator backend # # fredrik lundh, march 1998 # # fredrik@pythonware.com # http://www.pythonware.com # import sys,

The ImageGrab Module The ImageGrab module can be used to copy the contents of the screen or the clipboard to a PIL image memory. The current version works on Windows only. Functions  grab  ImageGrab.grab() ⇒ image ImageGrab.grab(bbox) ⇒ image (New in 1.1.3) Take a snapshot of the screen, and return an “RGB” image. The bounding box argument can be used

Element Library Functions March 22, 2004 | Fredrik Lundh ElementTree 1.3 may include a new module, ElementLib, with a number of convenient helper functions. The exact contents are yet to be determined; here are some of the current proposals (from various sources, in no specific order): Helpers to add subelements, with a nicer syntax. Wrappers to access

Idea In Progress: Dynamic Creation of Type Description In today’s Python, type records are implemented as ordinary struct‘s, using a flag field to indicate what version of the struct a given extension implements. You can see an example on this page (dead link) (Scroll down to the “static PyTypeObject NoddyType” definition). I propose to replace this with a

This module implements an in-memory file object. This object can be used as input or output to most functions that expect a standard file object. Example: Using the StringIO module to read from a static file # File: stringio-example-1.py import StringIO MESSAGE = “That man is depriving a village somewhere of a computer scientist.” file

ElementTree provides limited support for XPath expressions. The goal is to support a small subset of the abbreviated syntax; a full XPath engine is outside the scope of the core library. The 1.2 release supports simple element location paths. In its simplest form, a location path is one or more tag names, separated by slashes (/).

The ImageEnhance module contains a number of classes that can be used for image enhancement. Example  Vary the Sharpness of an Image import ImageEnhance enhancer = ImageEnhance.Sharpness(image) for i in range(8): factor = i / 4.0 enhancer.enhance(factor).show(“Sharpness %f” % factor) Also see the enhancer.py demo program in the Scripts directory. Interface  All enhancement classes implement a common interface, containing a single

Using the Image Class  The most important class in the Python Imaging Library is the Image class, defined in the module with the same name. You can create instances of this class in several ways; either by loading images from files, processing other images, or creating images from scratch. To load an image from a file, use

The Radiobutton is a standard Tkinter widget used to implement one-of-many selections. Radiobuttons can contain text or images, and you can associate a Python function or method with each button. When the button is pressed, Tkinter automatically calls that function or method. The button can only display text in a single font, but the text may span more than

The Simple Object Access Protocol (SOAP) is an XML-based protocol for “information exchange in distributed environments”. SOAP can be used in many different ways, but the most common approach is to use it for RPC requests over HTTP, where a client application sends a SOAP request message to a remote server, and the server returns a SOAP

The Python Imaging Library (PIL) adds image processing capabilities to your Python interpreter. This library supports many file formats, and provides powerful image processing and graphics capabilities. The current stable version is 1.1.7, released in November 2009. The next release will be 1.2, with “early 2011” as the release target. Prebuilt versions of PIL are available in most Linux

The Python Imaging Library handles raster images; that is, rectangles of pixel data. Bands An image can consist of one or more bands of data. The Python Imaging Library allows you to store several bands in a single image, provided they all have the same dimensions and depth. To get the number and names of bands

In this post, we will see how to create a simple Animation inside a canvas in Tkinter module in Python. The above code will give you the result as shown below:

Tkinter is a standard library in Python that is used to create Graphical User Interface (GUI) based desktop applications. It is pronounced (Tk inter).  You can learn more about Tkinter in the tkinter tutorial. How to create pop-up menus in tkinter?

When to use the Spinbox Widget The Spinbox widget can be used instead of an ordinary Entry, in cases where the user only has a limited number of ordered values to choose from. Note that the spinbox widget is only available in Python 2.3 and later when linked against Tk 8.4 or later. Also, note that several

The consumer interface is a simple “data sink” interface, used by standard Python modules such as xmllib and sgmllib. Other examples include the GZIP consumer and PIL’s ImageParser class. The consumer will typically convert incoming raw data in some way, and pass it on to a another layer. For example, XML parsers implementing this protocol usually parse the data stream into a stream of

This article discusses how to synchronize access to shared resources and otherwise coordinate execution of threads. Synchronizing Access to Shared Resources One important issue when using threads is to avoid conflicts when more than one thread needs to access a single variable or other resource. If you’re not careful, overlapping accesses or modifications from multiple