Binary package “libfakeroot” in ubuntu focal

tool for simulating superuser privileges - shared libraries

 fakeroot provides a fake "root environment" by means of LD_PRELOAD and
 SysV IPC (or TCP) trickery. It puts wrappers around getuid(), chown(),
 stat(), and other file-manipulation functions, so that unprivileged
 users can (for instance) populate .deb archives with root-owned files;
 various build tools use fakeroot for this by default.
 .
 This package contains the LD_PRELOAD libraries.