The gettext module provides a pure-Python implementation compatible with the GNU gettext library for message translation and catalog management. The tools available with the Python source distribution enable you to extract messages from a set of source files, build a message catalog containing translations, and use that message catalog to display an appropriate message for the user at runtime. Read more… This post is part of the Python Module of the Week series for Python 3.

The copy module includes two functions, copy() and deepcopy() , for duplicating existing objects. Read more… This post is part of the Python Module of the Week series for Python 3. See PyMOTW.com for more articles from the series.

dbm is a front-end for DBM-style databases that use simple string values as keys to access records containing strings. It uses whichdb() to identify databases, then opens them with the appropriate module. It is used as a back-end for shelve, which stores objects in a DBM database using pickle . Read more… This post is part of the Python Module of the Week series for Python 3. See PyMOTW.com for more articles from the series.

The concurrent.futures modules provides interfaces for running tasks using pools of thread or process workers. The APIs are the same, so applications can switch between threads and processes with minimal changes. Read more… This post is part of the Python Module of the Week series for Python 3. See PyMOTW.com for more articles from the series.

What’s new in 1.14.0? support pre-split command lines add quiet option (contributed by Brad Miller)

The functools module provides tools for adapting or extending functions and other callable objects, without completely rewriting them. Read more… This post is part of the Python Module of the Week series for Python 3. See PyMOTW.com for more articles from the series.

doctest tests source code by running examples embedded in the documentation and verifying that they produce the expected results. It works by parsing the help text to find examples, running them, then comparing the output text against the expected value. Many developers find doctest easier to use than unittest because, in its simplest form, there is no API to learn before using it. However, as the examples become more complex the lack of fixture management can make writing doctest tests more cumbersome than using unittest .

The random module provides a fast pseudorandom number generator based on the Mersenne Twister algorithm. Originally developed to produce inputs for Monte Carlo simulations, Mersenne Twister generates numbers with nearly uniform distribution and a large period, making it suited for a wide range of applications. Read more… This post is part of the Python Module of the Week series for Python 3. See PyMOTW.com for more articles from the series.

The dis module includes functions for working with Python bytecode by “disassembling” it into a more human-readable form. Reviewing the bytecodes being executed by the interpreter is a good way to hand-tune tight loops and perform other kinds of optimizations. It is also useful for finding race conditions in multi-threaded applications, since it can be used to estimate the point in the code where thread control may switch. Read more…

pprint contains a “pretty printer” for producing aesthetically pleasing views of data structures. The formatter produces representations of data structures that can be parsed correctly by the interpreter, and are also easy for a human to read. The output is kept on a single line, if possible, and indented when split across multiple lines. Read more… This post is part of the Python Module of the Week series for Python 3.