Python Language
- Getting started with Python Language
- Awesome Book
- Awesome Community
- Awesome Course
- Awesome Tutorial
- Awesome YouTube
- *args and **kwargs
- 2to3 tool
- Abstract Base Classes (abc)
- Abstract syntax tree
- Accessing Python source code and bytecode
- Alternatives to switch statement from other languages
- ArcPy
- Arrays
- Asyncio Module
- Attribute Access
- Audio
- Basic Curses with Python
- Basic Input and Output
- Binary Data
- Bitwise Operators
- Boolean Operators
- Call Python from C#
- Checking Path Existence and Permissions
- ChemPy - python package
- Classes
- CLI subcommands with precise help output
- Code blocks, execution frames, and namespaces
- Collections module
- Comments and Documentation
- Common Pitfalls
- Commonwealth Exceptions
- Comparisons
- Complex math
- Conditionals
- configparser
- Connecting Python to SQL Server
- Context Managers (“with” Statement)
- Copying data
- Counting
- Create virtual environment with virtualenvwrapper in windows
- Creating a Windows service using Python
- Creating Python packages
- ctypes
- Data Serialization
- Data Visualization with Python
- Database Access
- Date and Time
- Date Formatting
- Debugging
- Decorators
- Defining functions with list arguments
- Deployment
- Deque Module
- Descriptor
- Design Patterns
- Dictionary
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- Distribution
- Django
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- Enum
- Exceptions
- Exponentiation
- Files & Folders I/O
- Filter
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- Functional Programming in Python
- Functions
- Functools Module
- Garbage Collection
- Generators
- getting start with GZip
- graph-tool
- groupby()
- hashlib
- Heapq
- Hidden Features
- HTML Parsing
- Idioms
- ijson
- Immutable datatypes(int, float, str, tuple and frozensets)
- Importing modules
- Incompatibilities moving from Python 2 to Python 3
- Indentation
- Indexing and Slicing
- Input, Subset and Output External Data Files using Pandas
- Introduction to RabbitMQ using AMQPStorm
- IoT Programming with Python and Raspberry PI
- Iterables and Iterators
- Itertools Module
- JSON Module
- kivy - Cross-platform Python Framework for NUI Development
- Linked List Node
- Linked lists
- List
- List comprehensions
- List Comprehensions
- List destructuring (aka packing and unpacking)
- List slicing (selecting parts of lists)
- Logging
- Loops
- Manipulating XML
- Map Function
- Math Module
- Metaclasses
- Method Overriding
- Mixins
- Multidimensional arrays
- Multiprocessing
- Multithreading
- Mutable vs Immutable (and Hashable) in Python
- Neo4j and Cypher using Py2Neo
- Non-official Python implementations
- Operator module
- Operator Precedence
- Optical Character Recognition
- os.path
- Overloading
- Pandas Transform: Preform operations on groups and concatenate the results
- Parallel computation
- Parsing Command Line arguments
- Partial functions
- Performance optimization
- Pickle data serialisation
- Pillow
- pip: PyPI Package Manager
- Plotting with Matplotlib
- Plugin and Extension Classes
- Polymorphism
- PostgreSQL
- Processes and Threads
- Profiling
- Property Objects
- py.test
- pyaudio
- pyautogui module
- pygame
- Pyglet
- PyInstaller - Distributing Python Code
- Python and Excel
- Python Anti-Patterns
- Python concurrency
- Python Data Types
- Python HTTP Server
- Python Lex-Yacc
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- Python Server Sent Events
- Python speed of program
- Python Virtual Environment - virtualenv
- Queue Module
- Raise Custom Errors / Exceptions
- Random module
- Reading and Writing CSV
- Recursion
- Reduce
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- Searching
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- Security and Cryptography
- Set
- setup.py
- shelve
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- Simple Mathematical Operators
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- Sorting, Minimum and Maximum
- Sqlite3 Module
- Stack
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- String Methods
- String representations of class instances: __str__ and __repr__ methods
- Subprocess Library
- sys
- tempfile NamedTemporaryFile
- Templates in python
- The __name__ special variable
- The base64 Module
- The dis module
- The Interpreter (Command Line Console)
- The locale Module
- The os Module
- The pass statement
- The Print Function
- tkinter
- Tuple
- Turtle Graphics
- Type Hints
- Unicode
- Unicode and bytes
- Unit Testing
- Unzipping Files
- urllib
- Usage of "pip" module: PyPI Package Manager
- User-Defined Methods
- Using loops within functions
- Variable Scope and Binding
- virtual environment with virtualenvwrapper
- Virtual environments
- Web scraping with Python
- Web Server Gateway Interface (WSGI)
- Webbrowser Module
- Websockets
- Working around the Global Interpreter Lock (GIL)
- Working with ZIP archives
- Writing extensions
- Writing to CSV from String or List
Python Language 2to3 tool
Syntax
- $ 2to3 [-options] path/to/file.py
Parameters
| Parameter | Description |
|---|---|
| filename / directory_name | 2to3 accepts a list of files or directories which is to be transformed as its argument. The directories are recursively traversed for Python sources. |
| Option | Option Description |
| -f FIX, --fix=FIX | Specify transformations to be applied; default: all. List available transformations with --list-fixes |
| -j PROCESSES, --processes=PROCESSES | Run 2to3 concurrently |
| -x NOFIX, --nofix=NOFIX | Exclude a transformation |
| -l, --list-fixes | List available transformations |
| -p, --print-function | Change the grammar so that print() is considered a function |
| -v, --verbose | More verbose output |
| --no-diffs | Do not output diffs of the refactoring |
| -w | Write back modified files |
| -n, --nobackups | Do not create backups of modified files |
| -o OUTPUT_DIR, --output-dir=OUTPUT_DIR | Place output files in this directory instead of overwriting input files. Requires the -n flag, as backup files are unnecessary when the input files are not modified. |
| -W, --write-unchanged-files | Write output files even is no changes were required. Useful with -o so that a complete source tree is translated and copied. Implies -w. |
| --add-suffix=ADD_SUFFIX | Specify a string to be appended to all output filenames. Requires -n if non-empty. Ex.: --add-suffix='3' will generate .py3 files. |
Remarks
The 2to3 tool is an python program which is used to convert the code written in Python 2.x to Python 3.x code. The tool reads Python 2.x source code and applies a series of fixers to transform it into valid Python 3.x code.
The 2to3 tool is available in the standard library as lib2to3 which contains a rich set of fixers that will handle almost all code. Since lib2to3 is a generic library, it is possible to write your own fixers for 2to3.
