Django foreign key query, why it returns None? -

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When I try to query the foreign key using get (), then always Values ​​are not found, however I know they are set to 1 in DB. Am I missing something here? Should I do something different to get foreign key values?

This code looks like this: 

  class Car_to_brand (models.Model): brand_id = models.ForeignKey (brand, Db_column = 'brand_id') ... class brand (Models.Model): (id is not defined here but it is the primary key) ... Print Car_to_brand .__ dict __. Get (brand_id)   
 This will give me  {brand_id: none} , but it should be  {brand_id: 1} .   
 
 
 The problem is that you have named your field  brand_id  and not the brand There is no returning code (brand_id)  because the key is not in the  brand_id  dictionary if you print  car.__ signal___  If you do, you will see that it has  brand_id_id  instead.  
 However,  It is extremely unusual to use features that use  example .__ dict __. ()  . Instead try the following:  
  class car (models.Model): brand = models.ForeignKey (brand) # does not need to set db_column, brand_id is the default car. Brand_ID # is the brand ID (such as 1) This car is connected to car.brand # This is a brand instance

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