Man pages matching name http::entity::parser::octetstream in section 3pm:

HTTP::Entity::Parser::OctetStream.3pm.en	debian 10 / libhttp-entity-parser-perl
HTTP::Entity::Parser::OctetStream.3pm.en	debian 11 / libhttp-entity-parser-perl
HTTP::Entity::Parser::OctetStream.3pm.en	debian 12 / libhttp-entity-parser-perl