EPNM has a module to Manage Device Software Images, We used it to upgrade near of 5,000 ASR920 in 4 months in one of our customers, maybe it can help you:
https://www.cisco.com/c/en/us/td/docs/net_mgmt/epn_manager/7_0_0_GA/user/guide/bk_cisco_epnm_7_...
The Cobra SDK files are typically downloaded from a physical APIC appliance.
wget https://d1nmyq4gcgsfi5.cloudfront.net/fileMedia/1f3d41ce-d154-44e3-74c1-d6cf3b525eaa/acicobra-4.2_3h-py2.py3-none-any.whlwget https://d1nmyq4gcgsfi5.cloudfront.net/fi...
