django - python: model: can an attribute reference an attribute from the same model? -

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(this question win dumbiest question prize, i'll give try)

i have simple menu class in models:

class menu(models.model): name = models.charfield(null=false, blank=false,unique=true,max_length=50) url = models.charfield(null=false, blank=false, unique=true,max_length=100) sortorder = models.integerfield(null=false, blank=false, default=0)

this happily let me build 1 level of menu items.

if wanted go further , add level, how make items reference , id same model , make sure id not id of same item?

so there 2 questions:

1. how set foreignkey , id same class? referencing neither menu or self won't validated:

class menu(models.model): name = models.charfield(null=false, blank=false,unique=true,max_length=50) url = models.charfield(null=false, blank=false, unique=true,max_length=100) sortorder = models.integerfield(null=false, blank=false, default=0) **parent = models.foreignkey(menu)**

will throw:

nameerror: name 'menu' not defined

2. how make sure item's id not id of item?

try self

parent = models.foreignkey( 'self' )

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