code: def get_train_data(n_nodes=3, betas=1.0):
      np.random.seed(130947)
      baseline = np.random.rand(n_nodes)
      adjacency = np.random.rand(n_nodes, n_nodes)
      if isinstance(betas, (int, float)):
          betas = np.ones((n_nodes, n_nodes)) * betas
  
      sim = SimuHawkesExpKernels(
          adjacency=adjacency,
          decays=betas,
          baseline=baseline,
          verbose=False,
          seed=13487,
          end_time=3000,
      )
      sim.adjust_spectral_radius(0.8)
      adjacency = sim.adjacency
      sim.simulate()
  
      return sim.timestamps, baseline, adjacency
  
imports: import unittest
  import numpy
  from tick.base.inference import InferenceTest
  from tick.hawkes import SimuHawkesExpKernels
  from tick.hawkes.inference import HawkesExpKern
  from tick.hawkes.model.model_hawkes_expkern_leastsq import ModelHawkesExpKernLeastSq
  from tick.hawkes.model.model_hawkes_expkern_loglik import ModelHawkesExpKernLogLik
  from tick.prox import ProxNuclear
  from tick.prox import ProxPositive, ProxL1, ProxL2Sq, ProxElasticNet
  from tick.solver import AGD, GD, BFGS, SGD, SVRG
label_desc: Use image node_id 2 for calling the Test obj's underlying member method code with example usage: obj.get_train_data(n_nodes, betas) and returns: sim,  baseline,  adjacency