many to many - django manytomany filter question -

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grass,

I have a model that looks like this 

  class person (models.Model): name = models.CharField (empty = wrong, max_length = 100) friend = model. ManyToManyField ('self', empty = true, zero = true)
<

I tried 

  people_with_friends = person.objects.filter (friends = true)   
 thanks

What about it? 

  people_in different friends = person.objects.exclude (friend = none)

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