code: def test_type_str():
      assert_equal(ct._type_str((str,)), "str")
      assert_equal(ct._type_str(str), "str")
  
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 16 for calling a global function with example usage: test_type_str() without return types