old_contents: from os.path import join
  
  from .config.common import BaseSettings
  from .config.mixins import CompressMixin, DevMixin, ProdMixin, OpBeatMixin,\
      SecurityMixin, LogMixin, TestMixin, AuthenticationFeatureSwitch
  
  
  class DevDefaultSite(DevMixin, AuthenticationFeatureSwitch, BaseSettings):
      pass
  
  
  class TestDefaultSite(TestMixin, DevDefaultSite):
      pass
  
  
  class ProdDefaultSite(ProdMixin, CompressMixin, SecurityMixin, OpBeatMixin,
                        LogMixin, BaseSettings):
      """
      Settings for live and demo hosting.
      """
      pass
  
  
  class ProdDevDefaultSite(AuthenticationFeatureSwitch, ProdDefaultSite):
      """
      Settings for qcat-dev hosting.
      """
      pass
  
new_contents: from os.path import join
  
  from .config.common import BaseSettings
  from .config.mixins import CompressMixin, DevMixin, ProdMixin, OpBeatMixin,\
      SecurityMixin, LogMixin, TestMixin, AuthenticationFeatureSwitch
  
  
  class DevDefaultSite(DevMixin, AuthenticationFeatureSwitch, BaseSettings):
      pass
  
  
  class TestDefaultSite(TestMixin, DevDefaultSite):
      pass
  
  
  class ProdDefaultSite(ProdMixin, AuthenticationFeatureSwitch, CompressMixin,
                        SecurityMixin, OpBeatMixin, LogMixin, BaseSettings):
      """
      Settings for live and demo hosting.
      """
      pass
  
  
  class ProdDevDefaultSite(AuthenticationFeatureSwitch, ProdDefaultSite):
      """
      Settings for qcat-dev hosting.
      """
      pass
  
subject: Add AuthenticationFeatureSwitch to ProdDefaultSite