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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 _subtract(summary, o):
 """Remove object o from the summary by subtracting it's size."""

    found = False
    row = [_repr(o), 1, _getsizeof(o)]
    for r in summary:
        if r[0] == row[0]:
            (r[1], r[2]) = (r[1] - row[1], r[2] - row[2])
            found = True
    if not found:
        summary.append([row[0], -row[1], -row[2]])
    return summary