def _check_warn_threshold(self, time_to, event_dict):
if time_to["<STR_LIT>"] <= self.warn_threshold:<EOL><INDENT>warn_message = self.py3.safe_format(self.format_notification, event_dict)<EOL>self.py3.notify_user(warn_message, "<STR_LIT>", self.warn_timeout)<EOL><DEDENT>
Checks if the time until an event starts is less than or equal to the
warn_threshold. If True, issue a warning with self.py3.notify_user.