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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 open_recruitment(self, n=1):
 """Open a connection to AWS MTurk and create a HIT."""

        logger.info("Opening MTurk recruitment for {} participants".format(n))
        if self.is_in_progress:
            raise MTurkRecruiterException(
                "Tried to open_recruitment on already open recruiter."
            )

        if self.hit_domain is None:
            raise MTurkRecruiterException("Can't run a HIT from localhost")

        self.mturkservice.check_credentials()

        if self.config.get("assign_qualifications"):
            self._create_mturk_qualifications()

        hit_request = {
            "max_assignments": n,
            "title": self.config.get("title"),
            "description": self.config.get("description"),
            "keywords": self._config_to_list("keywords"),
            "reward": self.config.get("base_payment"),
            "duration_hours": self.config.get("duration"),
            "lifetime_days": self.config.get("lifetime"),
            "ad_url": self.ad_url,
            "notification_url": self.config.get("notification_url"),
            "approve_requirement": self.config.get("approve_requirement"),
            "us_only": self.config.get("us_only"),
            "blacklist": self._config_to_list("qualification_blacklist"),
            "annotation": self.config.get("id"),
        }
        hit_info = self.mturkservice.create_hit(**hit_request)
        if self.config.get("mode") == "sandbox":
            lookup_url = (
                "https://workersandbox.mturk.com/mturk/preview?groupId={type_id}"
            )
        else:
            lookup_url = "https://worker.mturk.com/mturk/preview?groupId={type_id}"

        return {
            "items": [lookup_url.format(**hit_info)],
            "message": "HIT now published to Amazon Mechanical Turk",
        }