code: def forward(self, x):
      gx, gy = add_coord(x, self.data_format)
      if self.data_format == "NCHW":
          y = paddle.concat([x, gx, gy], axis=1)
      else:
          y = paddle.concat([x, gx, gy], axis=-1)
      y = self.conv(y)
      return y
  
imports: import paddle
  import paddle.nn
  import paddle.nn.functional
  from ppdet.core.workspace import register, serializable
  from ppdet.modeling.layers import DropBlock
  from ppdet.modeling.ops import get_act_fn
  from ..backbones.darknet import ConvBNLayer
  from ..shape_spec import ShapeSpec
  from ..backbones.csp_darknet import BaseConv, DWConv, CSPLayer
label_desc: Use image node_id 2 for calling the CoordConv obj's underlying member method code with example usage: obj.forward(x) and returns: y