Make tricircle function test work with python3

Change-Id: I0400cff6f98797f21f81b787958c13b271ac730f
Signed-off-by: zhangchi <zhangchi@szzt.com.cn>
Co-Authored-By: tangzhuo <ztang@hnu.edu.cn>

.zuul.yaml

@@ -10,6 +10,21 @@
       - openstack/neutron
       - openstack/networking-sfc
 
+- job:
+    name: tricircle-functional-python3
+    parent: legacy-dsvm-base
+    run: playbooks/tricircle-dsvm-functional/run.yaml
+    post-run: playbooks/tricircle-dsvm-functional/post.yaml
+    timeout: 7800
+    required-projects:
+      - openstack/devstack-gate
+      - openstack/tricircle
+      - openstack/neutron
+      - openstack/networking-sfc
+    vars:
+      devstack_localrc:
+        USE_PYTHON3: true
+
 - job:
     name: tricircle-multiregion
     parent: legacy-dsvm-base-multinode
@@ -61,6 +76,7 @@
               - openstack/neutron
               - openstack/networking-sfc
         - tricircle-functional
+        - tricircle-functional-python3
         - tricircle-multiregion
     gate:
       jobs: