code: def forward(self, x):
      conv0 = self.conv0_ssh(x)
      conv1 = self.conv1_ssh(conv0)
      conv2 = self.conv2_ssh(conv1)
      conv3 = self.conv3_ssh(conv2)
      conv4 = self.conv4_ssh(conv3)
      concat = paddle.concat([conv0, conv2, conv4], axis=1)
      return F.relu(concat)
  
imports: import paddle
  import paddle.nn.functional
  from paddle import ParamAttr
  import paddle.nn
  from paddle.nn.initializer import KaimingNormal
  from ppdet.core.workspace import register, serializable
  from ..shape_spec import ShapeSpec
label_desc: Use image node_id 2 for calling the SSH obj's underlying member method code with example usage: obj.forward(x) and returns: F