make test: Loopback interface CRUD test

Change-Id: I0581da7a682bfe4dd6520ecf1b2ea6bd8c20b1b3
Signed-off-by: Matej Klotton <mklotton@cisco.com>
diff --git a/test/framework.py b/test/framework.py
index 324a64c..e364a8f 100644
--- a/test/framework.py
+++ b/test/framework.py
@@ -355,9 +355,10 @@
     @classmethod
     def create_pg_interfaces(cls, interfaces):
         """
-        Create packet-generator interfaces
+        Create packet-generator interfaces.
 
-        :param interfaces: iterable indexes of the interfaces
+        :param interfaces: iterable indexes of the interfaces.
+        :returns: List of created interfaces.
 
         """
         result = []
@@ -371,10 +372,10 @@
     @classmethod
     def create_loopback_interfaces(cls, interfaces):
         """
-        Create loopback interfaces
+        Create loopback interfaces.
 
-        :param interfaces: iterable indexes of the interfaces
-
+        :param interfaces: iterable indexes of the interfaces.
+        :returns: List of created interfaces.
         """
         result = []
         for i in interfaces: