code: def __init__(self, ch_in, ch_out):
      super(ConvBlock, self).__init__()
      self.conv = nn.Sequential(
          nn.Conv2D(ch_in, ch_out, kernel_size=3, stride=1, padding=1),
          nn.BatchNorm2D(ch_out),
          nn.ReLU(),
          nn.Conv2D(ch_out, ch_out, kernel_size=3, stride=1, padding=1),
          nn.BatchNorm2D(ch_out),
          nn.ReLU(),
      )
  
imports: import paddle
  import paddle.nn
  from paddleseg.cvlibs import manager
  from paddleseg.models import layers
  from paddleseg import utils
  import numpy
label_desc: Use image node_id 1 to create a new ConvBlock object from inherited base classes: nn with example: obj = ConvBlock(ch_in, ch_out)