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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 _build_credentials(self, nexus_switches):
 """Build credential table for Rest API Client. :param nexus_switches: switch config :returns credentials: switch credentials list """

        credentials = {}
        for switch_ip, attrs in nexus_switches.items():
            credentials[switch_ip] = (
                attrs[const.USERNAME], attrs[const.PASSWORD],
                attrs[const.HTTPS_VERIFY], attrs[const.HTTPS_CERT],
                None)
            if not attrs[const.HTTPS_VERIFY]:
                LOG.warning("HTTPS Certificate verification is "
                            "disabled. Your connection to Nexus "
                            "Switch %(ip)s is insecure.",
                            {'ip': switch_ip})
        return credentials