python - Django @staticmethod sum of two fields -


I have a quick question that I am trying to add a field to a model which is the sum of 2 fields . For example: 

  class MyModel (models.Model) fee = models I thought I could add a @staticmethod inside the model:  
  @ Staticmethod def fee_total (auto): Returns self.fi + self.fi_stuff   
 but I think the model's "fee_total" Can not use using the field:  
  model  
 Cheers  
 Cheers    
 
 
 
 I think that you want to add a method to your model, so it Can the.  
  @staticmethod  is a decorator that declares the method for  class , then what is the difference?  
 Well, long story short, static methods do not have any special examples, give an example for the object  class  object, by me  class  
 such as  @property  before mention of everyone A decorator has been used to make a method as a variable ... so you do not have to explicitly use  ()   
, you want to do this:  
  class MyModel (models.Model) fee = models.DecimalField () fee_gst = models.DecimalField () @property def fee_total (auto): Return self.fee + self.fee_gst   
 Although the document is a Take a long approach:  
  class MyModel (models.Model) = fee model. DecimalField () fee_gst = models.DecimalField () def _fee_total (self): return self.fee + Self.fee_gst fee_total = property (_fee_total)   
 Both methods are quite similar, Use as a small hand.  
 Hope it helps. / P>

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