Hi, i have installed mirdeep2 on ubuntu following the tutorial but unable to extract files from miRBase folder in the linux (the folder exists) . After giving the command extract_miRNAs hairpin.fa ssc > hairpin_ssc.fa, it showed extract_miRNAs: command not found. Tried with perl extract_miRNAs.pl mature.fa cel mature, showed-- `mature.fa not found No such file or directory at extract_miRNAs.pl line 36.``. please suggest a solution