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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 transform_padding(pad_width):
 """Helper function to convert padding format for pad operator. """

    num_pad_values = len(pad_width)
    onnx_pad_width = [0]*num_pad_values

    start_index = 0
    # num_pad_values will always be multiple of 2
    end_index = int(num_pad_values/2)
    for idx in range(0, num_pad_values):
        if idx % 2 == 0:
            onnx_pad_width[start_index] = pad_width[idx]
            start_index += 1
        else:
            onnx_pad_width[end_index] = pad_width[idx]
            end_index += 1

    return onnx_pad_width