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How does a Python list grow in memory?

Q: How does a Python list grow in memory?

A `list` is a **dynamic array**: a contiguous block of **pointers** to objects, plus a length and a (larger) **capacity**. When you `append` past the capacity, CPython allocates a **bigger block** (growing geometrically, not by one), copies the pointers over, and frees the old block: len 4 / cap 4 append → len 5 / cap 8 <rect class='d-box-a

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