snmplabs.com site is down, so Borrow Missing/failed MIBS does not work

[archjeb]

snmplabs.com site appears to be down. So some functions of mibdump.py will not work.

[Costya-Y]

Still down, or maybe down again

[lextm]

You can read etingof/pysnmp#429 for more details.

Switch to pysmi-lextudio package and try again.