def METHOD_NAME(trim, fastqc):
    if trim and fastqc:
        return( expand(fastq_dir+"/{sample}{read}.fastq.gz", sample = samples, read = reads) +
                expand("FastQC_trimmed/{sample}{read}_fastqc.html", sample = samples, read = reads) )
    elif trim:
        return( expand(fastq_dir+"/{sample}{read}.fastq.gz", sample = samples, read = reads) )
    else:
        return([])