Install libparallel-forkmanager-perl by entering the following commands in the terminal:
sudo apt update sudo apt install libparallel-forkmanager-perl
simple parallel processing fork manager for Perl
Parallel::ForkManager Perl module is intended for use in operations that can be done in parallel where the number of processes to be forked off should be limited. Typical use is a downloader which will be retrieving hundreds/thousands of files.