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LookupError

LookupError

What does this code mean?

Code LookupError · An issue reported by Python.

Official explanation · Original text

The base class for the exceptions that are raised when a key or index used on a mapping or sequence is invalid: IndexError, KeyError. This can be raised directly by codecs.lookup().

Troubleshooting and diagnostic links

First check that the document's product, version, and environment match your situation.

Source and terms of use

Built-in Exceptions — Python 3.15.2 documentation ↗

Creator: Python Software Foundation
License: Python Software Foundation License Version 2
Checked on: 2026-11-12

Modifications: English prose extracted; whitespace normalized; Korean context and classified official links added. Python code examples not redistributed.

Source details · Original licenses and notices