code: def flag?(flag)
        key = canonical_key(flag)
        state = flags[key] if flags?
        state = environment_flag?(key) if state.nil?
  
        case state
        when nil then nil
        else state.to_s == 'true'
        end
      end
docs: Returns the boolean state of the flag as found in options[:answers],
   or if not found in the answers, then it checks for an environment variable.
  
   @param String flag key
   @return [Boolean,nil] boolean true or false unless not found at all, then nil.