code: def test_call_twice(self, teardown):
      x0 = Input()
      x1 = Input()
      step = DummySISO()
      y0 = step(x0)
      y1 = step(x1)
  
      assert isinstance(y0, DataPlaceholder)
      assert isinstance(y1, DataPlaceholder)
      assert y0.name == "DummySISO_0:0/0"
      assert y1.name == "DummySISO_0:1/0"
  
imports: from contextlib import contextmanager
  from functools import partial
  import pytest
  from sklearn.base import TransformerMixin, BaseEstimator
  from baikal import Input, Step, set_config
  from baikal._core.data_placeholder import DataPlaceholder
  from baikal._core.step import InputStep
  from tests.helpers.fixtures import teardown
  from tests.helpers.dummy_steps import DummyMIMO, DummySISO, DummyEstimator
  from tests.helpers.sklearn_steps import LogisticRegression, PCA
label_desc: Use image node_id 11 for calling the TestStep obj's underlying member method code with example usage: obj.test_call_twice(teardown) without return types