how to filter items in django

I have some users in my application where some are admin and some are suppliers, I will like to filter only those that are suppliers. I have tried using some queryset but I am not getting it. I will also like some recommendation where I can learn more about to filter objects in Django or python. Thanks

models.py

class User(AbstractBaseUser, PermissionsMixin):
    email = models.EmailField(max_length=254, unique=True)
    is_staff = models.BooleanField(default=False)
    is_superuser = models.BooleanField(default=False)
    is_active = models.BooleanField(default=True)
    last_login = models.DateTimeField(null=True, blank=True)
    date_joined = models.DateTimeField(auto_now_add=True)

    # CUSTOM USER FIELDS
    firstname = models.CharField(max_length=30)
    lastname = models.CharField(max_length=30)
    telephone = models.IntegerField(blank=True, null=True)

    USERNAME_FIELD = 'email'
    EMAIL_FIELD = 'email'
    REQUIRED_FIELDS = []

    def get_absolute_url(self):
        return "/users/%i/" % (self.pk)

class user_type(models.Model):
    is_admin = models.BooleanField(default=False)
    is_supplier = models.BooleanField(default=False)
    user = models.OneToOneField(User, on_delete=models.CASCADE)

    def __str__(self):
        if self.is_supplier == True:
            return User.get_email(self.user) + " - is_supplier"
        else:
            return User.get_email(self.user) + " - is_admin"

views.py

def Viewsupplier(request):

    suppliers = User.objects.filter(i am getting stuck here with the appriopriate filter)  
    context = {"suppliers":suppliers}
    print(suppliers)

    return render(request, 'core/view-suppliers.html', context)