code: def test_2_no_terms():
      """
      Tests the length of the latent variable vector for an ARIMAX model
      with no AR or MA terms, and two predictors, and tests that the values
      are not nan
      """
      model = ARIMAX(
          formula="y ~ x1 + x2", data=data, ar=0, ma=0, family=t()
      )
      x = model.fit()
      assert len(model.latent_variables.z_list) == 5
      lvs = np.array([i.value for i in model.latent_variables.z_list])
      assert len(lvs[np.isnan(lvs)]) == 0
  
imports: import numpy
  import pandas
  from pyflux.arma import ARIMAX
  from pyflux.families import t
label_desc: Use image node_id 18 for calling a global function with example usage: test_2_no_terms() without return types