Cldr.List.known_list_formats
You're seeing just the function
known_list_formats, go back to Cldr.List module for more information.
Return the list of known list formats.
Example
iex> Cldr.List.known_list_formats()
[:or, :or_narrow, :or_short, :standard, :standard_narrow,
:standard_short, :unit, :unit_narrow, :unit_short]