code: def test_normalize_within():
      norm_data = normalize(data, normalize="within")
      assert np.allclose([np.mean(i, axis=0) for i in norm_data], 0)
  
file_path: hypertools/tests/test_normalize.py
imports: import numpy
  from hypertools.tools.normalize import normalize
  from hypertools.plot.plot import plot
label_desc: Use image node_id 3 for calling a global function with example usage: test_normalize_within() without return types