code: def test_erode():
      x = np.zeros((1, 3, 3, 1), dtype=np.float32)
      x[:, 1, 1] = 1
      x = tf.convert_to_tensor(x)
      expected = tf.zeros((1, 3, 3, 1))
      out = erode(x, 3)
      assert tf.math.reduce_all(out == expected)
  
imports: import os
  import tempfile
  import numpy
  import onnxruntime
  import psutil
  import pytest
  import tensorflow
  from doctr.file_utils import CLASS_NAME
  from doctr.io import DocumentFile
  from doctr.models import detection
  from doctr.models.detection._utils import dilate, erode
  from doctr.models.detection.predictor import DetectionPredictor
  from doctr.models.preprocessor import PreProcessor
  from doctr.models.utils import export_model_to_onnx
label_desc: Use image node_id 6 for calling a global function with example usage: test_erode() without return types