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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def print_single(line, rev):
 """ print single reads to stderr """

    if rev is True:
        seq = rc(['', line[9]])[1]
        qual = line[10][::-1]
    else:
        seq = line[9]
        qual = line[10]
    fq = ['@%s' % line[0], seq, '+%s' % line[0], qual]
    print('\n'.join(fq), file = sys.stderr)