Pysnmp is a python implementation of snmp v.1/v.2c engine; both 2.x and 4.x branches of pysnmp are available in debian.

pysnmp-se (speed enhanced) is a fork of the pysnmp 3.4.x branch with various speed enhancements, the most important being the replacement of string-based oids with tuple-based oids.

this makes pysnmp-se slightly incompatible with pysnmp.