text: # This code is part of Qiskit.
  #
  # (C) Copyright IBM 2019.
  #
  # This code is licensed under the Apache License, Version 2.0. You may
  # obtain a copy of this license in the LICENSE.txt file in the root directory
  # of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
  #
  # Any modifications or derivative works of this code must retain this
  # copyright notice, and modified files need to carry a notice indicating
  # that they have been altered from the originals.
  
  """
  Fake Singapore device (20 qubit).
  """
  
  import os
  from qiskit.test.mock import fake_pulse_backend
  
  
  class FakeSingapore(fake_pulse_backend.FakePulseBackend):
      """A fake Singapore backend.
  
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      """
  
      dirname = os.path.dirname(__file__)
      conf_filename = "conf_singapore.json"
      props_filename = "props_singapore.json"
      defs_filename = "defs_singapore.json"
      backend_name = "fake_singapore"
  
  
  class FakeLegacySingapore(fake_pulse_backend.FakePulseLegacyBackend):
      """A fake Singapore backend.
  
      00 ↔ 01 ↔ 02 ↔ 03 ↔ 04
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      15 ↔ 16 ↔ 17 ↔ 18 ↔ 19
      """
  
      dirname = os.path.dirname(__file__)
      conf_filename = "conf_singapore.json"
      props_filename = "props_singapore.json"
      defs_filename = "defs_singapore.json"
      backend_name = "fake_singapore"
  