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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 scatterAlign(seq1, seq2, window=7):
 """ Visually align two sequences. """

    d1 = defaultdict(list)
    d2 = defaultdict(list)
    for (seq, section_dict) in [(seq1, d1), (seq2, d2)]:
        for i in range(len(seq) - window):
            section = seq[i:i + window]
            section_dict[section].append(i)
    matches = set(d1).intersection(d2)
    print('%i unique matches' % len(matches))
    x = []
    y = []
    for section in matches:
        for i in d1[section]:
            for j in d2[section]:
                x.append(i)
                y.append(j)
    # plt.cla()  # clear any prior graph
    plt.gray()
    plt.scatter(x, y)
    plt.xlim(0, len(seq1) - window)
    plt.ylim(0, len(seq2) - window)
    plt.xlabel('length %i bp' % (len(seq1)))
    plt.ylabel('length %i bp' % (len(seq2)))
    plt.title('Dot plot using window size %i\n(allowing no mis-matches)' %
              window)
    plt.show()