code: def test_type_local_max():
      f = basic_field()
      f.field = f.field.astype(np.float32)
      idx, depth = f.get_local_maxima(th=0)
      assert_array_equal(idx, np.array([999]))
  
imports: import numpy
  import numpy.random
  from numpy.testing import assert_array_equal
  from ..field import field_from_coo_matrix_and_data, field_from_graph_and_data
  from ..graph import wgraph_from_3d_grid
label_desc: Use image node_id 6 for calling a global function with example usage: test_type_local_max() without return types