python - Django CharField primary key doesn't work, creating rowid primary key automatically -

i using django models sqlite database.

i defined charfield primary key (for example name of attribute a) physical database synced django shows primary key rowid instead of a.

i tried dropping table , re-sync couple of time still same.

why?

class testtable(models.model):     = models.charfield(max_length=10, primary_key=true, db_column='a') 

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django version 1.8.3