Introduction to pyupgrade

pyupgrade is a powerful tool designed to automatically upgrade your Python code. Whether you’re working on an old project or starting new ones, pyupgrade helps ensure your code adheres to modern Python syntax and practices. It makes refactoring simpler and less error-prone, allowing you to keep up with Python development standards effortlessly.

Key APIs of pyupgrade

1. Upgrading String Formatting

Transform your old string formatting into f-strings for better readability and performance.

  old_code = "Hello, {} {}!".format(first_name, last_name)
  new_code = f"Hello, {first_name} {last_name}!"

2. Type Annotations

Convert PEP 484 type comments to function annotations.

  old_code = 
  def greet(name: str):
    # type: (str) -> None
    print(f"Hello, {name}!")

  new_code = 
  def greet(name: str) -> None:
    print(f"Hello, {name}!")

3. Lambda to Function

Convert simple lambdas to def functions.

  old_code = 
  add = lambda x, y: x + y

  new_code = 
  def add(x, y):
    return x + y

4. Standard Library Imports

Update deprecated module imports to their modern equivalents.

  old_code = 
  import collections

  new_code = 
  from collections import namedtuple

5. Unpacking Generalizations

Use Python 3.5’s extended unpacking generalizations.

  old_code = 
  a, b = [1, 2]

  new_code = 
  first, *rest = [1, 2, 3, 4]

Application Example

Here is a simple application demonstrating pyupgrade in action:

  old_code = 
  import collections

  Point = collections.namedtuple('Point', 'x y')
  point = Point(1, 2)
  message = "This point is: {}.".format(point)
  print(message)

  new_code = 
  from collections import namedtuple

  Point = namedtuple('Point', 'x y')
  point = Point(1, 2)
  message = f"This point is: {point}."
  print(message)

As demonstrated, pyupgrade can make your code more modern, readable, and maintainable with just a few changes!

Hash: e9be99331ea2874f66ecd280b5c916ea71cd9bdcbe2adef61270df32aab73118