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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 needle(reads):
 """ Run a Needleman-Wunsch alignment and return the two sequences. @param reads: An iterable of two reads. @return: A C{Reads} instance with the two aligned sequences. """

    from tempfile import mkdtemp
    from shutil import rmtree

    dir = mkdtemp()

    file1 = join(dir, 'file1.fasta')
    with open(file1, 'w') as fp:
        print(reads[0].toString('fasta'), end='', file=fp)

    file2 = join(dir, 'file2.fasta')
    with open(file2, 'w') as fp:
        print(reads[1].toString('fasta'), end='', file=fp)

    out = join(dir, 'result.fasta')

    Executor().execute("needle -asequence '%s' -bsequence '%s' -auto "
                       "-outfile '%s' -aformat fasta" % (
                           file1, file2, out))

    # Use 'list' in the following to force reading the FASTA from disk.
    result = Reads(list(FastaReads(out)))
    rmtree(dir)

    return result