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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_input(proto):
 """Get input size """

    layer = caffe_parser.get_layers(proto)
    if len(proto.input_dim) > 0:
        input_dim = proto.input_dim
    elif len(proto.input_shape) > 0:
        input_dim = proto.input_shape[0].dim
    elif layer[0].type == "Input":
        input_dim = layer[0].input_param.shape[0].dim
        layer.pop(0)
    else:
        raise ValueError('Cannot find input size')

    assert layer[0].type != "Input", 'only support single input'
    # We assume the first bottom blob of first layer is the output from data layer
    input_name = layer[0].bottom[0]
    return input_name, input_dim, layer