text: """Test fixtures."""
  
  from builtins import super
  
  from napalm_base.test import conftest as parent_conftest
  from napalm_base.test.double import BaseTestDouble
  from napalm_base.utils import py23_compat
  
  from napalm_exaros import exaros
  from napalm_exaros.ssh import ExaROSSSH
  
  import pytest
  
  
  @pytest.fixture(scope='class')
  def set_device_parameters(request):
      """Set up the class."""
      def fin():
          request.cls.device.close()
      request.addfinalizer(fin)
  
      request.cls.driver = exaros.ExaROSDriver
      request.cls.patched_driver = PatchedExaROSDriver
      request.cls.vendor = 'exaros'
      parent_conftest.set_device_parameters(request)
  
  
  def pytest_generate_tests(metafunc):
      """Generate test cases dynamically."""
      parent_conftest.pytest_generate_tests(metafunc, __file__)
  
  
  class PatchedExaROSDriver(exaros.ExaROSDriver):
      """Patched ExaROS Driver."""
  
      def __init__(self, hostname, username, password,
                   timeout=60, optional_args=None):
          """Patched ExaROS Driver constructor."""
          super().__init__(hostname, username, password, timeout, optional_args)
  
          self.patched_attrs = ['connection']
          self.connection = FakeExaROSDevice()
  
      def open(self):
          """Open a connection to the device."""
          pass
  
      def close(self):
          """Close the connection to the device."""
          pass
  
      def is_alive(self):
          """Return a flag with the state of the SSH connection."""
          return {'is_alive': True}
  
  
  class FakeExaROSDevice(BaseTestDouble, ExaROSSSH):
      """ExaROS device test double."""
  
      def select_delay_factor(self, delay_factor):
          """Set dummy delay_factor."""
          return 1
  
      def config_mode(self):
          """Enter into configuration mode."""
          pass
  
      def send_command(self, command, **kwargs):
          """Fake send_command."""
          filename = '{}.txt'.format(self.sanitize_text(command))
          full_path = self.find_file(filename)
          result = self.read_txt_file(full_path)
          return py23_compat.text_type(result)
  