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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 remove_in_progress_notifications(self, master=True):
 """Remove all notifications from notifications_in_progress :param master: remove master notifications only if True (default value) :type master: bool :param force: force remove all notifications except if False :type force: bool :return:None """

        for notification in list(self.notifications_in_progress.values()):
            if master and notification.contact:
                continue
            # Do not remove some specific notifications
            if notification.type in [u'DOWNTIMESTART', u'DOWNTIMEEND', u'DOWNTIMECANCELLED',
                                     u'CUSTOM', u'ACKNOWLEDGEMENT']:
                continue
            self.remove_in_progress_notification(notification)