code: def test_tupleof():
      c = ct.EnsureTupleOf(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 12 for calling a global function with example usage: test_tupleof() without return types