#!usr/bin/perl use English '-no_match_vars'; use strict; use warnings; use Bio::Perl; my $database = 'genbank'; my $format = 'fasta'; my @accessions = ( "bunch", "of", "accession", "numbers"); for my $i ( 0 ... 2000 ) { my $entry_id = $accessions[$i]; eval { my $sequence = get_sequence($database, $entry_id); write_sequence( '>-', $format, $sequence ); }; if ( $EVAL_ERROR ) { # Log Error here if an error occured print {*STDERR} "Could not download sequence: [$entry_id]\n"; } # If you need to keep track of count my $count = $i + 1; }