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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_dim_size(start, stop, step):
 """Given start, stop, and stop, calculate the number of elements of this slice."""

    assert step != 0
    if step > 0:
        assert start < stop
        dim_size = (stop - start - 1) // step + 1
    else:
        assert stop < start
        dim_size = (start - stop - 1) // (-step) + 1
    return dim_size