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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 get_diff(left, right):
 """Get the difference of two summaries. Subtracts the values of the right summary from the values of the left summary. If similar rows appear on both sides, the are included in the summary with 0 for number of elements and total size. If the number of elements of a row of the diff is 0, but the total size is not, it means that objects likely have changed, but not there number, thus resulting in a changed size. """

    res = []
    for row_r in right:
        found = False
        for row_l in left:
            if row_r[0] == row_l[0]:
                res.append([row_r[0], row_r[1] - row_l[1], row_r[2] - row_l[2]])
                found = True
        if not found:
            res.append(row_r)

    for row_l in left:
        found = False
        for row_r in right:
            if row_l[0] == row_r[0]:
                found = True
        if not found:
            res.append([row_l[0], -row_l[1], -row_l[2]])
    return res