def METHOD_NAME(a, b):
    aline = []
    bline = []
    for tag, i1, i2, j1, j2 in difflib.SequenceMatcher(a=a, b=b).get_opcodes():
        if tag == "equal":
            aline.append(escape(a[i1:i2]))
            bline.append(escape(b[j1:j2]))
            continue
        aline.append('<span class="highlight">%s</span>' % (escape(a[i1:i2]),))
        bline.append('<span class="highlight">%s</span>' % (escape(b[j1:j2]),))
    return "".join(aline), "".join(bline)