code: def test_predict_is_length():
      """
      Tests that the length of the predict IS dataframe is equal to no of steps h
      """
      model = ARIMAX(formula="y ~ x1", data=data, ar=2, ma=2)
      x = model.fit()
      assert model.predict_is(h=5).shape[0] == 5
  
imports: import numpy
  import pandas
  from pyflux.arma import ARIMAX
label_desc: Use image node_id 5 for calling a global function with example usage: test_predict_is_length() without return types