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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 check_connections(self):
 """Check connection between OpenStack to Nexus device."""

        switch_connections = self._mdriver.get_all_switch_ips()

        for switch_ip in switch_connections:
            state = self._mdriver.get_switch_ip_and_active_state(switch_ip)
            config_failure = self._mdriver.get_switch_replay_failure(
                const.FAIL_CONFIG, switch_ip)
            contact_failure = self._mdriver.get_switch_replay_failure(
                const.FAIL_CONTACT, switch_ip)
            LOG.debug("check_connections() thread %(thid)d, switch "
                      "%(switch_ip)s state %(state)s "
                      "contact_failure %(contact_failure)d "
                      "config_failure %(config_failure)d ",
                      {'thid': threading.current_thread().ident,
                       'switch_ip': switch_ip, 'state': state,
                       'contact_failure': contact_failure,
                       'config_failure': config_failure})
            try:
                # Send a simple get nexus type to determine if
                # the switch is up
                nexus_type = self._driver.get_nexus_type(switch_ip)
            except Exception:
                if state != const.SWITCH_INACTIVE:
                    LOG.error("Lost connection to switch ip "
                        "%(switch_ip)s", {'switch_ip': switch_ip})
                    self._mdriver.set_switch_ip_and_active_state(
                        switch_ip, const.SWITCH_INACTIVE)
                else:
                    self._mdriver.incr_switch_replay_failure(
                        const.FAIL_CONTACT, switch_ip)
            else:
                if state == const.SWITCH_RESTORE_S2:
                    try:
                        self._mdriver.configure_next_batch_of_vlans(switch_ip)
                    except Exception as e:
                        LOG.error("Unexpected exception while replaying "
                                  "entries for switch %(switch_ip)s, "
                                  "Reason:%(reason)s ",
                                  {'switch_ip': switch_ip, 'reason': e})
                        self._mdriver.register_switch_as_inactive(
                            switch_ip, 'replay next_vlan_batch')
                    continue

                if state == const.SWITCH_INACTIVE:
                    self._configure_nexus_type(switch_ip, nexus_type)
                    LOG.info("Re-established connection to switch "
                        "ip %(switch_ip)s",
                        {'switch_ip': switch_ip})

                    self._mdriver.set_switch_ip_and_active_state(
                        switch_ip, const.SWITCH_RESTORE_S1)
                    self.replay_config(switch_ip)

                    # If replay failed, it stops trying to configure db entries
                    # and sets switch state to inactive so this caller knows
                    # it failed.  If it did fail, we increment the
                    # retry counter else reset it to 0.
                    if self._mdriver.get_switch_ip_and_active_state(
                        switch_ip) == const.SWITCH_INACTIVE:
                        self._mdriver.incr_switch_replay_failure(
                            const.FAIL_CONFIG, switch_ip)
                        LOG.warning("Replay config failed for "
                                    "ip %(switch_ip)s",
                                    {'switch_ip': switch_ip})
                    else:
                        self._mdriver.reset_switch_replay_failure(
                            const.FAIL_CONFIG, switch_ip)
                        self._mdriver.reset_switch_replay_failure(
                            const.FAIL_CONTACT, switch_ip)
                        LOG.info("Replay config successful for "
                            "ip %(switch_ip)s",
                            {'switch_ip': switch_ip})