Add a cropping layer to the model.
        The cropping layer have two functional modes:

            - When it has 1 input blob, it crops the input blob based
              on the 4 parameters [left, right, top, bottom].
            - When it has 2 input blobs, it crops the first input blob based
              on the dimension of the second blob with an offset.

        Parameters
        ----------
        name: str
            The name of this layer.
        left: int
            Number of elements to be cropped on the left side of the input blob.
            When the crop layer takes 2 inputs, this parameter is ignored.
        right: int
            Number of elements to be cropped on the right side of the input blob.
            When the crop layer takes 2 inputs, this parameter is ignored.
        top: int
            Number of elements to be cropped on the top of the input blob.
            When the crop layer takes 2 inputs, this parameter is ignored.
        bottom: int
            Number of elements to be cropped on the bottom of the input blob.
            When the crop layer takes 2 inputs, this parameter is ignored.
        offset: [int]
            Offset along the height and width directions when the crop layer takes 2 inputs. Must be a list of length 2.
            When the crop layer takes 1 input, this parameter is ignored.
        input_names: [str]
            The input blob name(s) of this layer. Must be either a list of 1 string (1 input crop layer),
            or a list of 2 strings (2-input crop layer).
        output_name: str
            The output blob name of this layer.

        See Also
        --------
        add_padding, add_convolution, add_pooling

def add_crop(self, name, left, right, top, bottom, offset, input_names,
            output_name):
        """
        Add a cropping layer to the model.
        The cropping layer have two functional modes:

            - When it has 1 input blob, it crops the input blob based
              on the 4 parameters [left, right, top, bottom].
            - When it has 2 input blobs, it crops the first input blob based
              on the dimension of the second blob with an offset.

        Parameters
        ----------
        name: str
            The name of this layer.
        left: int
            Number of elements to be cropped on the left side of the input blob.
            When the crop layer takes 2 inputs, this parameter is ignored.
        right: int
            Number of elements to be cropped on the right side of the input blob.
            When the crop layer takes 2 inputs, this parameter is ignored.
        top: int
            Number of elements to be cropped on the top of the input blob.
            When the crop layer takes 2 inputs, this parameter is ignored.
        bottom: int
            Number of elements to be cropped on the bottom of the input blob.
            When the crop layer takes 2 inputs, this parameter is ignored.
        offset: [int]
            Offset along the height and width directions when the crop layer takes 2 inputs. Must be a list of length 2.
            When the crop layer takes 1 input, this parameter is ignored.
        input_names: [str]
            The input blob name(s) of this layer. Must be either a list of 1 string (1 input crop layer),
            or a list of 2 strings (2-input crop layer).
        output_name: str
            The output blob name of this layer.

        See Also
        --------
        add_padding, add_convolution, add_pooling
        """
        spec = self.spec
        nn_spec = self.nn_spec

        # Add a new layer
        spec_layer = nn_spec.layers.add()
        spec_layer.name = name
        for input_name in input_names:
            spec_layer.input.append(input_name)
        spec_layer.output.append(output_name)
        spec_layer_params = spec_layer.crop

        # Set the parameters
        offset = [0,0] if len(input_name) == 1 else offset
        spec_layer_params.offset.extend(offset)
        height_border = spec_layer_params.cropAmounts.borderAmounts.add()
        height_border.startEdgeSize = top
        height_border.endEdgeSize = bottom
        width_border = spec_layer_params.cropAmounts.borderAmounts.add()
        width_border.startEdgeSize = left
        width_border.endEdgeSize = right