code: def test_get_plates():
      def get_plate_names():
          plates = get_plates()
          assert isinstance(plates, tuple)
          return {f.name for f in plates}
  
      assert get_plate_names() == set()
      with pyro.plate("foo", 5):
          assert get_plate_names() == {"foo"}
          with pyro.plate("bar", 3):
              assert get_plate_names() == {"foo", "bar"}
  
imports: import torch
  import pyro
  import pyro.poutine
  from pyro.poutine.runtime import get_mask, get_plates
  from tests.common import assert_equal
label_desc: Use image node_id 2 for calling a global function with example usage: test_get_plates() and returns: unknown