code: def test_expm(B):
      if B.__class__.__name__[:3] != "csc":
          return
  
      Bmat = scipy.sparse.csc_matrix(B)
  
      C = spla.expm(B)
  
      assert isinstance(C, scipy.sparse.sparray)
      npt.assert_allclose(C.todense(), spla.expm(Bmat).todense())
  
imports: import pytest
  import numpy
  import numpy.testing
  import scipy.sparse
  import scipy.sparse.linalg
  from scipy._lib._util import VisibleDeprecationWarning
label_desc: Use image node_id 20 for calling a global function with example usage: test_expm(B) without return types