code: def forward(self, x):
      x = x[::-1]
      y = []
      last_x = None
      for i, s in enumerate(x):
          if last_x is not None:
              last_x = F.interpolate(
                  last_x,
                  size=s.shape[-2:],
                  mode="bilinear",
                  align_corners=True,
              )
              s = s + last_x
          s = self.projects[i](s)
          y.append(s)
          last_x = s
  
      return y[::-1]
  
imports: import paddle
  import paddle.nn
  import paddle.nn.functional
  from numbers import Integral
  from paddle import ParamAttr
  from paddle.regularizer import L2Decay
  from paddle.nn.initializer import Normal, Constant
  from ppdet.core.workspace import register
  from ppdet.modeling.shape_spec import ShapeSpec
  from ppdet.modeling.ops import channel_shuffle
  from ..None import layers
label_desc: Use image node_id 2 for calling the IterativeHead obj's underlying member method code with example usage: obj.forward(x) and returns: y