python - Define a django model which use in a foreign key a specific instance of an other model -


let's take example problem : models of blog. have django models : 

class category(models.model):     name = models.charfield(max_length=30)  class article(models.model):     title = models.charfield(max_length=30)     content = models.textfield()     category = models.foreignkey('category')

my problem how define other model use specific category. example, how define cook model, based on article model inheritance, used category 'cook'.

thank you.

to complete comment: 

class category(models.model):     name = models.charfield(max_length=10)  def cook_category():     return category.objects.get(name='cook')  class cookarticle(models.model):     #your model     category = models.foreignkey(category, default=cook_category)

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