Python uses ARC plus a tracing GC for dealing with cycles, same as PHP: https://devguide.python.org/garbage_collector/

Perl uses ARC with no tracing GC, so you have to handle cycles yourself: https://www.perlmonks.org/?node_id=1173079

TCL uses ARC, and apparently doesn't need a tracing GC because it is impossible to create cycles in it: https://wiki.tcl-lang.org/page/Garbage+collection