/usr/lib/erlang/lib/snmp-4.21.1/include/ is in erlang-dev 1:14.b.4-dfsg-1ubuntu1.
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/usr/lib/erlang/lib/snmp-4.21.1/include/INET-ADDRESS-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/OTP-SNMPEA-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/RFC1213-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMP-COMMUNITY-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMP-FRAMEWORK-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMP-MPD-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMP-NOTIFICATION-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMP-TARGET-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMP-USER-BASED-SM-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMP-USM-AES-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMP-VIEW-BASED-ACM-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMPv2-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMPv2-TC.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/SNMPv2-TM.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/STANDARD-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/TRANSPORT-ADDRESS-MIB.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/snmp_tables.hrl
/usr/lib/erlang/lib/snmp-4.21.1/include/snmp_types.hrl