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unpigz --to-stdout /project/microbiome/data_queue/seq/TRNL1/rawdata/TRNL1_R1.fastq.gz | split -l 40000000 5000000 -d --suffix-length=3 --additional-suffix=.fastq - TRNL1_R1_
unpigz --to-stdout /project/microbiome/data_queue/seq/TRNL1/rawdata/TRNL1_R2.fastq.gz | split -l 40000000 5000000 -d --suffix-length=3 --additional-suffix=.fastq - TRNL1_R2_
...