/usr/lib/x86_64-linux-gnu/libftp.so.3 is in ftplib3 3.1-1-9build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libftp.so.3.1
/usr/lib/x86_64-linux-gnu/libftp.so.3.1