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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def trust_mod_times(self):
 """ 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 """

        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)))