class_docstr: UNet model for segmentation task.
class_docstr_tok: ["UNet","model","for","segmentation","task","."]
code: def default_flax_model_config(self):
      return ml_collections.ConfigDict(
          {
              "model": dict(
                  padding="SAME",
                  use_batch_norm=False,
                  block_size=(64, 128, 256, 512),
                  data_dtype_str="float32",
              )
          }
      )
  
imports: import functools
  from typing import Tuple
  import flax.linen
  import jax.numpy
  import ml_collections
  from scenic.model_lib.base_models.segmentation_model import SegmentationModel
  from scenic.model_lib.layers import nn_layers
  from scenic.model_lib.layers import nn_ops
label_desc: Use image node_id 2 for calling the UNetSegmentationModel obj's underlying member method code with example usage: obj.default_flax_model_config() and returns: ml_collections