Template:US statename
Script error: No such module "U.S. States".
The Template:US_statename invokes the Lua Module:U.S._States to find the U.S. State name for specified 2-letter abbreviation in parameter 1. An invalid abbreviation returns an error, as a newline with no text.
Performance considerations
The Template:US_statename runs at the rate of 500 abbreviations per second, and is intended to run 50% faster than the equivalent markup-based Template:US_State_Abbrev, which uses a large #switch function to match the 2-letter abbreviations to the related state names.