initial unittest for osm_nbi.instance_topics

Change-Id: Ib38b3e6625014c8641e7cadce69624f46b41d1ac
Signed-off-by: tierno <alfonso.tiernosepulveda@telefonica.com>
diff --git a/requirements.txt b/requirements.txt
index 64c7079..426e430 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -17,4 +17,5 @@
 requests
 git+https://osm.etsi.org/gerrit/osm/common.git#egg=osm-common
 git+https://osm.etsi.org/gerrit/osm/IM.git#egg=osm-im
+aiohttp==0.20.2