Python's len() Function

Christopher Trudeau

In many situations, you’ll need to find the number of items stored in a data structure. Python’s built-in function len() is the tool that will help you with this task.

There are some cases in which the use of len() is straightforward. However, there are other times when you’ll need to understand how this function works in more detail and how to apply it to different data types.

In this course, you’ll learn how to:

  • Find the length of built-in data types using len()
  • Use len() with third-party data types
  • Provide support for len() with user-defined classes

What’s Included:

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About Christopher Trudeau

Christopher has a passion for the Python language and writes for Real Python. He is a consultant who helps advise organizations on how to improve their technical teams.

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