len() Across Types

len() with Different Types Checking Empty Collections len() in Common Patterns Here are practical patterns using len() that appear frequently in data engineering code: The batch processing example shows how len() helps divide work into manageable chunks. The validation example shows how len() ensures data has the expected structure before processing. Both patterns are common in real-world data pipelines. Whether you are processing millions of records or validating user input, len() is your first line of defense against malformed data. len() on Nested Structures When working with nested structures, len() only counts the top-level elements, not nested contents: Understanding this behavior is crucial for data engineering. When you have a list of records, len() tells you how many records you h