code: def test_nominal_case():
      """Nominal flow: can decode field successfully"""
      expected = np.random.rand(10, 10)
      row = {"matrix": NdarrayCodec().encode(MatrixField, expected)}
  
      actual = decode_row(row, MatrixSchema)["matrix"]
  
      np.testing.assert_equal(actual, expected)
  
file_path: petastorm/petastorm/tests/test_decode_row.py
imports: from decimal import Decimal
  import numpy
  import pytest
  from pyspark.sql.types import DoubleType
  from petastorm.codecs import NdarrayCodec, ScalarCodec
  from petastorm.unischema import UnischemaField, Unischema
  from petastorm.utils import decode_row, DecodeFieldError
label_desc: Use image node_id 1 for calling a global function with example usage: test_nominal_case() without return types