# File lib/fog/aws/models/efs/mount_target.rb, line 48
        def save
          requires :file_system_id, :subnet_id
          params = {}
          params.merge!('IpAddress' => self.ip_address) if self.ip_address
          params.merge!('SecurityGroups' => @security_groups) if @security_groups

          merge_attributes(service.create_mount_target(self.file_system_id, self.subnet_id, params).body)
        end