code: func isStringInSlice(s []string, what string) bool {
  	for i := range s {
  		if s[i] == what {
  			return true
  		}
  	}
  	return false
  }
docs: // isStringInSlice returns whether a given string "what" is contained in a
  // slice, "s".
  //
  // isStringInSlice is copied from "github.com/xeipuuv/gojsonschema/utils.go"