language property
language
The ISO-639-1 alpha 2 code in lower case for the language,
optionally followed by a hyphen and the ISO-3166-1 alpha 2 code for
the region in upper case; e.g. "en" for English, or "en-US" for
American English versus "en-AU" for Australian English.
Implementation
CodeableConcept get language => throw _privateConstructorUsedError;