Python’s built-in exec() function allows you to execute arbitrary Python code from a string or compiled code input. The exec() function can be handy when you need to run dynamically generated Python code, but it can be pretty dangerous if you use it carelessly. In this tutorial, you’ll learn not only how to use exec(), but just as importantly, when it’s okay to use this function in your code. In this tutorial, you’ll learn how to: Work with Python’s built-in […]

If you’re new to programming or come from a programming language other than Python, you may be looking for the best way to check whether a string contains another string in Python. Identifying such substrings comes in handy when you’re working with text content from a file or after you’ve received user input. You may want to perform different actions in your program depending on whether a substring is present or not. In this tutorial, you’ll focus on the most […]

When your Python code is too slow, you need to identify the bottleneck that’s causing it: you need to understand what your code is doing. Luckily, beyond pre-existing profiling tools, there are also a variety of ways you can poke and prod Python programs to get a better understanding of what they’re doing internally. This allows you to do one-time introspection, add profiling facilities to your program that you can turn on and off, build custom tools, and in general […]