Ankh.HTTP.Request.fetch_header_values
You're seeing just the function
fetch_header_values, go back to Ankh.HTTP.Request module for more information.
Link to this function
fetch_header_values(request, header)
Specs
fetch_header_values(t(), Ankh.HTTP.header_name()) :: [Ankh.HTTP.header_value()]
See Ankh.HTTP.fetch_header_values/2.