code: def init(cls):
      cls.res2 = cls.mod2.fit()
      mod = GLM(
          cls.endog,
          cls.exogc,
          offset=0.5 * cls.exog[:, cls.idx_c].squeeze(),
      )
      mod.exog_names[:] = ["const", "x2", "x3", "x4"]
      cls.res1 = mod.fit()
      cls.idx_p_uc = np.arange(cls.exogc.shape[1])
  
imports: import warnings
  import numpy
  from numpy.testing import assert_allclose, assert_equal
  from statsmodels.genmod.families import family
  from statsmodels.genmod.generalized_linear_model import GLM
  from statsmodels.regression.linear_model import OLS, WLS
  from statsmodels.tools.sm_exceptions import ValueWarning
  from statsmodels.tools.tools import add_constant
label_desc: Use image node_id 1 for calling the TestGLMGaussianOffset obj's underlying member method code with example usage: obj.init(cls) without return types