code: func (self *DocumentBase) Delete() error {
  
  	if self.Id.Valid() {
  
  		self.SetDeleted(true)
  
  		return self.Save()
  	}
  
  	return errors.New("Invalid object id")
  }
docs: // Calling this method will not remove the object from the database. Instead the deleted flag is set to true.
  // So you can use bson.M{"deleted":false} in your query to filter those documents.