MagyarWhat is Python? Full Summary
Python is an interpreted, object-oriented, high-level programing language with dynamic semantics. Its high-level inbuilt data structures, combined with dynamic typing and dynamic binding, make it very attractive for Rapid Application Development, also as to be used as a scripting or glue language to attach existing components together. Python’s simple, easy to find out syntax emphasizes readability and thus reduces the value of program maintenance. Python supports modules and packages, which inspires program modularity and code reuse. The Python interpreter and therefore the extensive standard library are available in source or binary form for free of charge for all major platforms, and may be freely distributed.
Often, programmers fall crazy with Python due to the increased productivity it provides. Since there’s no compilation step, the edit-test-debug cycle is incredibly fast. Debugging Python programs is easy: a bug or bad input will never cause a segmentation fault. Instead, when the interpreter discovers a mistake , it raises an exception. When the program doesn’t catch the exception, the interpreter prints a stack trace. A source level debugger allows inspection of local and global variables, evaluation of arbitrary expressions, setting breakpoints, stepping through the code a line at a time, and so on. The debugger is written in Python itself, testifying to Python’s introspective power. On the opposite hand, often the quickest thanks to debug a program is to feature a couple of print statements to the source: the fast edit-test-debug cycle makes this easy approach very effective.
Python Latest Version check What’s New In Python 3.9
Summary – Release highlights
New syntax features:
PEP 584, union operators added to dict;
PEP 585, type hinting generics in standard collections;
PEP 614, relaxed grammar restrictions on decorators.
New built-in features:
PEP 616, string methods to get rid of prefixes and suffixes.
New features within the standard library:
PEP 593, flexible function and variable annotations;
os.pidfd_open() added that permits process management without races and signals.
Interpreter improvements:
PEP 573, fast access to module state from methods of C extension types;
PEP 617, CPython now uses a replacement parser supported PEG;
a number of Python builtins (range, tuple, set, frozenset, list, dict) are now sped up using PEP 590 vectorcall;
garbage collection doesn’t block on resurrected objects;
a number of Python modules (_abc, audioop, _bz2, _codecs, _contextvars, _crypt, _functools, _json, _locale, math, operator, resource, time, _weakref) now use multiphase initialization as defined by PEP 489;
a number of ordinary library modules (audioop, ast, grp, _hashlib, pwd, _posixsubprocess, random, select, struct, termios, zlib) are now using the stable ABI defined by PEP 384.
New library modules:
PEP 615, the IANA zone Database is now present within the standard library within the zoneinfo module;
an implementation of a topological kind of a graph is now provided within the new graphlib module.
Release process changes:
PEP 602, CPython adopts an annual release cycle.
You should check for DeprecationWarning in your code
When Python 2.7 was still supported, tons of functionality in Python 3 was kept for backward compatibility with Python 2.7. With the top of Python 2 support, these backward compatibility layers are removed, or are going to be removed soon. Most of them emitted a DeprecationWarning warning for several years. for instance , using collections.Mapping rather than collections.abc.Mapping emits a DeprecationWarning since Python 3.3, released in 2012.
Test your application with the -W default command-line choice to see DeprecationWarning and PendingDeprecationWarning, or maybe with -W error to treat them as errors. Warnings Filter are often wont to ignore warnings from third-party code.
Python 3.9 is that the last version providing those Python 2 backward compatibility layers, to offer longer to Python projects maintainers to arrange the removal of the Python 2 support and add support for Python 3.9.
Aliases to Abstract Base Classes within the collections module, like collections.Mapping alias to collections.abc.Mapping, are kept for one last release for backward compatibility. they’re going to be faraway from Python 3.10.
More generally, attempt to run your tests within the Python Development Mode which helps to organize your code to form it compatible with subsequent Python version.
Note: variety of pre-existing deprecations were removed during this version of Python also . Consult the Removed section.
