code: def test_yx(self, y, x):
      # Ensure that product is called with args in the order that they appear
      # in the function's parameter list.
      self.yx_invocations.append((y, x))
  
imports: from itertools import product
  from unittest import TestCase
  from numpy import array, empty
  from zipline._protocol import BarData
  from zipline.finance.asset_restrictions import NoRestrictions
  from zipline.finance.order import Order
  from zipline.testing import check_arrays, make_alternating_boolean_array, make_cascading_boolean_array, parameter_space
  from zipline.testing.fixtures import WithConstantEquityMinuteBarData, WithDataPortal, ZiplineTestCase
  from zipline.testing.slippage import TestingSlippage
  from zipline.testing.predicates import wildcard, instance_of
  from zipline.utils.numpy_utils import bool_dtype
label_desc: Use image node_id 4 for calling the TestParameterSpace obj's underlying member method code with example usage: obj.test_yx(y, x) without return types