Man pages matching name pmtrimnamespace in section 3:

pmTrimNameSpace.3.en	debian 10 / libpcp3-dev
pmtrimnamespace.3.en	debian 10 / libpcp3-dev
pmTrimNameSpace.3.en	debian 11 / libpcp3-dev
pmTrimNameSpace.3.en	debian 12 / libpcp3-dev