Multiple Return Values

Python functions can return multiple values by returning a tuple. The caller can then unpack these values into separate variables. This pattern is cleaner than returning a dictionary or list when you have a fixed number of related values to compute and return together. In data engineering, you often need to compute several related metrics from the same data in a single pass. Rather than calling separate functions (which would iterate over the data multiple times), you compute everything in one function and return all the results. This is more efficient and keeps related logic together. Returning Multiple Values Multi-Return Patterns Multiple returns are common when processing data and computing related metrics: Ignoring Unwanted Values Keeping as Tuple You can also receive all values as a

About This Interactive Section

This section is part of the Functions: Intermediate lesson on DataDriven, a free data engineering interview prep platform. Each section includes explanations, worked examples, and hands-on code challenges that execute in real time. SQL queries run against a live PostgreSQL database. Python runs in a sandboxed Docker container. Data modeling problems validate against interactive schema canvases. All content is framed around what data engineering interviewers actually test at companies like Meta, Google, Amazon, Netflix, Stripe, and Databricks.

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