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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 bam_to_fastq_pair(in_file, target_region, pair):
 """Generator to convert BAM files into name, seq, qual in a region. """

    space, start, end = target_region
    bam_file = pysam.Samfile(in_file, "rb")
    for read in bam_file:
        if (not read.is_unmapped and not read.mate_is_unmapped
                and bam_file.getrname(read.tid) == space
                and bam_file.getrname(read.mrnm) == space
                and read.pos >= start and read.pos <= end
                and read.mpos >= start and read.mpos <= end
                and not read.is_secondary
                and read.is_paired and getattr(read, "is_read%s" % pair)):
            seq = Seq.Seq(read.seq)
            qual = list(read.qual)
            if read.is_reverse:
                seq = seq.reverse_complement()
                qual.reverse()
            yield read.qname, str(seq), "".join(qual)