from django.contrib.auth.models import User
class Profile(models.Model):
    login = models.ForeignKey(User, unique=True)
    first_name = models.CharField(u'First name',max_length=200)
    middle_name = models.CharField(u'Middle name',max_length=200)
    def __unicode__(self):
        return '%s %s ' % (self.first_name,  self.middle_name)
class Data(models.Model):
    login =  models.ForeignKey(User)
    f = models.PositiveIntegerField(u'f', default=2)
    def __unicode__(self):
        return str(self.f)

In [14]: Data.objects.filter(f__in=[4,10]).values('login','f')
Out[14]: [{'login': 3L, 'f': 10L}, {'login': 2L, 'f': 4L}]

In [12]: User.objects.all()
Out[12]: [<User: ivan>, <User: user1>, <User: user2>]
In [13]: Profile.objects.all()
Out[13]: [<Profile: Марья  Ивановна >, <Profile: Сергей  Сергеевич >]

Data.objects.filter(f__in=[4,10]).values('login__firstname','login__middle_name')

 Data.objects.filter(f__in=[4,10]).values('f','login__profile__first_name','login__profile__middle_name')