Description of problem:
Create apps on devenv-stage_491, upgrade the server and run datastore migration. Try to upgrade the gears via oo-admin-upgrade, python 2.7 app will fail and found following error in the upgrade_error log:

"message": "Errors encountered executing step upgrade_script_python"

            "upgrade_script_python": {
                "context": {
                    "cartridge": "python", 
                    "rc": 1, 
                    "stderr": "/var/lib/openshift/52566db35534c5a5db0001ce/python//usr/versions/2.7/bin/upgrade: line 63: OPENSHIFT_DEPENDENCIES_DIR: unbound variable\n", 
                    "stdout": ""
                }, 
                "errors": [
                    "Upgrade script for python returned a non-zero exit code (1)"
                ], 
                "status": "incomplete"
            }



Version-Release number of selected component (if applicable):
devenv-stage_491 to devenv_3881

How reproducible:
always

Steps to Reproduce:
1.Create test data on devenv-stage_491
2.Upgrade the server and run compatible migration for datastore
3.Upgrade the gears via oo-admin-upgrade
# oo-admin-upgrade upgrade-node --version 3.0.35 --ignore-cartridge-version

Actual results:
Python 2.7 app will fail during the gear upgrade.

Expected results:
App should be upgraded successfully.

Additional info: