code: func (s *SendBounceInput) Validate() error {
  	invalidParams := request.ErrInvalidParams{Context: "SendBounceInput"}
  	if s.BounceSender == nil {
  		invalidParams.Add(request.NewErrParamRequired("BounceSender"))
  	}
  	if s.BouncedRecipientInfoList == nil {
  		invalidParams.Add(request.NewErrParamRequired("BouncedRecipientInfoList"))
  	}
  	if s.OriginalMessageId == nil {
  		invalidParams.Add(request.NewErrParamRequired("OriginalMessageId"))
  	}
  	if s.BouncedRecipientInfoList != nil {
  		for i, v := range s.BouncedRecipientInfoList {
  			if v == nil {
  				continue
  			}
  			if err := v.Validate(); err != nil {
  				invalidParams.AddNested(fmt.Sprintf("%s[%v]", "BouncedRecipientInfoList", i), err.(request.ErrInvalidParams))
  			}
  		}
  	}
  	if s.MessageDsn != nil {
  		if err := s.MessageDsn.Validate(); err != nil {
  			invalidParams.AddNested("MessageDsn", err.(request.ErrInvalidParams))
  		}
  	}
  
  	if invalidParams.Len() > 0 {
  		return invalidParams
  	}
  	return nil
  }
docs: // Validate inspects the fields of the type to determine if they are valid.