How do get the different values that takes an attribute with a django query?

I have this Model in django :

class Post(models.Model):
    title = models.CharField(max_length=255)
    category = mode开发者_JS百科ls.CharField(max_length=255)

I would like to get the different values that are used in the category attribute.

For example, if we consider this db :

Post(title = "title 1", category="foo")
Post(title = "title 2", category="bar")
Post(title = "title 3", category="foo")

the query should give me ("foo", "bar")

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Use distinct() and values_list():

Post.objects.values_list('category', flat=True).distinct();