code: def trust_mod_times(self):
          
          on_appveyor = coerce_boolean(os.environ.get('APPVEYOR', 'False'))
          return coerce_boolean(self.get(property_name='trust_mod_times',
                                         environment_variable='PIP_ACCEL_TRUST_MOD_TIMES',
                                         configuration_option='trust-mod-times',
                                         default=(not on_appveyor)))
docs: Whether to trust file modification times for cache invalidation.
  
          - Environment variable: ``$PIP_ACCEL_TRUST_MOD_TIMES``
          - Configuration option: ``trust-mod-times``
          - Default: :data:`True` unless the AppVeyor_ continuous integration
                     environment is detected (see `issue 62`_).
  
          .. _AppVeyor: http://www.appveyor.com
          .. _issue 62: https://github.com/paylogic/pip-accel/issues/62