libc6-udeb 2.31-0ubuntu9.8 (amd64 binary) in ubuntu focal

 Contains the standard libraries that are used by nearly all programs on
 the system. This package includes shared versions of the standard C library
 and the standard math library, as well as many others.
 .
 This package contains a minimal set of libraries needed for the Debian
 installer. Do not install it on a normal system.