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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 delete_trigger(self, trigger):
 """ Deletes from the Alert API the trigger record identified by the ID of the provided `pyowm.alertapi30.trigger.Trigger`, along with all related alerts :param trigger: the `pyowm.alertapi30.trigger.Trigger` object to be deleted :type trigger: `pyowm.alertapi30.trigger.Trigger` :returns: `None` if deletion is successful, an exception otherwise """

        assert trigger is not None
        assert isinstance(trigger.id, str), "Value must be a string"
        status, _ = self.http_client.delete(
            NAMED_TRIGGER_URI % trigger.id,
            params={'appid': self.API_key},
            headers={'Content-Type': 'application/json'})