code: def test_listof():
      c = ct.EnsureListOf(str)
      assert_equal(c(["a", "b"]), ["a", "b"])
      assert_equal(c(["a1", "b2"]), ["a1", "b2"])
      assert_equal(c("a1 b2"), ["a1 b2"])
  
file_path: datalad/datalad/tests/test_constraints.py
imports: from datalad.tests.utils_pytest import assert_equal, assert_raises
  from ..support import constraints
label_desc: Use image node_id 11 for calling a global function with example usage: test_listof() without return types