Python 3.5 is really old...

bin/oca_install_addons

@@ -29,7 +29,13 @@ cat test-requirements.txt
 
 # To be sure to install addons from this repo if they are dependencies of dependencies,
 # we create a constraints file with local directory references to the addons to test.
-oca_list_addons_to_test_as_reqs >> test-constraints.txt
+if python -c 'import sys; sys.exit(sys.version_info < (3,6))' ; then
+    # python >= 3.6
+    oca_list_addons_to_test_as_reqs >> test-constraints.txt
+else
+    # old python where pip does not support URL constraints
+    touch test-constraints.txt
+fi
 cat test-constraints.txt
 
 # show pip config