all Python 3Exceptionsexception

LookupError

built-in exceptions

Base class for lookup errors: IndexError and KeyError.

Syntax

raise LookupError

Catch it directly only where the code works over sequences and mappings alike; elsewhere the specific IndexError or KeyError is sharper and won't hide a third, unexpected case. Less obvious: an unknown codec name also lands here — 'abc'.encode('nosuch') raises LookupError, not ValueError.

Examples

try:
    raise LookupError
except LookupError as e:
    print(type(e).__name__)   # → LookupError

See also

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