When you’re building a Docker image for your Python application, you’re building on top of an existing image—and there are many possible choices. There are OS images like Ubuntu, and there are the many different variants of the python base image. Which one should you use? Which one is better? There are many choices, and it may not be obvious which is the best for your situation. So to help you make a choice that fits your needs, in this […]

In this section, you’ll learn how to define a function that takes an optional argument. Functions with optional arguments offer more flexibility in how you can use them. You can call the function with or without the argument, and if there is no argument in the function call, then a default value is used. Default Values Assigned to Input Parameters You can modify the function add_item() so that the parameter quantity has a default value: # optional_params.py shopping_list = {} […]

If you often work with lists in Python, then you probably know that they don’t perform fast enough when you need to pop and append items on their left end. Python’s collections module provides a class called deque that’s specially designed to provide fast and memory-efficient ways to append and pop item from both ends of the underlying data structure. Python’s deque is a low-level and highly optimized double-ended queue that’s useful for implementing elegant, efficient, and Pythonic queues and […]

The release of Python 3.10 is just around the corner, and, as we reported in May, the new interpreter will be getting several improvements to error messages. The work on improved errors continues in Python 3.11. Yes, that’s right! Even though Python 3.10 won’t be released until October, work on Python 3.11 is already under way! Fine-Grained Error Locations in Tracebacks Pablo Galindo, the release manager for Python 3.10 and 3.11, shared in a July 16, 2021 tweet that he […]