code: def _generate_matrices(self):
      state = np.random.get_state()
      np.random.seed(self._matrix_gen_seed)
      self._A = np.random.randn(self._input_dim, self._output_dim)
      np.random.set_state(state)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import pytest
  import numpy
  import torch
  import torch.nn
  import torch.optim
  from torch.utils.data import Dataset, DataLoader
  import bluefog.torch
  from bluefog.common import topology_util
label_desc: Use image node_id 2 for calling the LinearProblemBuilder obj's underlying member method code with example usage: obj._generate_matrices() without return types