Union and Intersect in Django

class Tag(models.Model):
  name = models.CharField(maxlength=100)

class Blog(models.Model):
  name = models.CharField(maxlength=100)
  tags =  models.ManyToManyField(Tag)

Simple models just to ask my question.

I wonder how can i query blogs using tags in two different ways.

• Blog entries that are tagged with "tag1" or "tag2": Blog.objects.filter(tags_in=[1,2]).distinct()
• Blog objects that are tagged with "tag1" and "tag2" : ?
• Blog objects that are tagged with exactly "tag1" and "tag2" and nothing else : ??

Tag and Blog is just used for an example.