Please replace that awful extension magic with regular use* functions from EAPI.
commit 780e1a2faff8e62942b7a516b811be519f3ae2aa Author: Lars Wendler <polynomial-c@gentoo.org> Date: Wed Feb 22 10:42:17 2017 net-ftp/pure-ftpd: Converted away from confutils eclass (bug #610482). Package-Manager: Portage-2.3.3, Repoman-2.3.1