INSTALLED_APPS = [
                    ...,
                    'rest_framework',
                    'subscriptions_api',
                    ]

url(r'^api/subscriptions/', include('subscriptions_api.urls')),

from subscriptions_api.models import PlanCost, UserSubscription

class PaymentModel(models.Model):
     cost = models.ForeignKey(PlanCost, null=True, on_delete=models.SET_NULL)

#Create SubscriptionPlan and PlanCost from django admin
#A user is added to the group on subscription plan after subscription is activated.
#SubscriptionPlan features field can be json of dict e.g {"can_send_message": true } that can be accessed
#directly from the subscription plan obj

#New user can automatically be subscribed to a plan cost by setting DFS_DEFAULT_PLAN_COST_ID in settings.py  to ID of a plan cost
# you want user to be subscribed to

#you can subscribe user to a plan by
subscription = cost.setup_user_subscription(request.user, active=False, no_multiple_subscription=True)

#with active=False user subscription would not be activated immediately use active=True for otherwise

#no_multiple_subscription prevents user from being subscribed to more than one plan at time previous plan will be removed

#After successful user payment you can activate_subscription by using subscription above or

subscription = UserSubscription.objects.get(user=request.user)

#or for user with multiple active subscription when no_multiple_subscription=False

subscription = UserSubscription.objects.get(user=request.user, cost=cost)

subscription.activate() #Activate  subscription and user is added to the group on subscription plan which can use for your views and general       #django permissions

if user_subscripton.plan_cost.plan.can_send_message: #or Access json feature list of a subscription plan
    send_message()

#deactivate subscription. User is removed from Group on subscription

subscription.deactivate()

#You can also record transaction or swap out BaseSubscriptionTransaction in base_models.py to implement or link with a payment model

class SubscriptionTransaction(BaseSubscriptionTransaction):
     cryptocurrency_payments = GenericRelation(CryptoCurrencyPayment)
     paypal_id = models.OneToOneField(PayPalModel)
     stripe_id = models.OneToOneField(StripeModel)

subscription.record_transaction()

#Lastly override notifications in notification.py to send emails to user regarding their payment and subscription