No. This error comes from your 'requests' library and means that you cannot reach your device or resource.
Max retries exceeded with url: /mgmt/tm/sys/ (Caused by NewConnectionError('<urllib3.connection.VerifiedHTTPSConnection object at 0x7f078c5b66a0>: Failed to establish a new connection: [Errno -2] Name or service not known',))
Insecure warnings looks like this:
InsecureRequestWarning: Unverified HTTPS request is being made to host '<BIG-IP Device>'. Adding certificate verification is strongly advised. See: https://urllib3.readthedocs.io/en/latest/advanced-usage.html#ssl-warnings
InsecureRequestWarning,
But these warnings should be disabled by default.
So check your destination IP, user privileges and so on.
BTW, if these answers were helpful don't forget to mark the answer as 'the best' or give some upvotes.
KR,
Dario.