def _get_rrd(server, vm_uuid):
    """Return the VM RRD XML as a string."""
    try:
        xml = urllib.urlopen("%s://%s:%s@%s/vm_rrd?uuid=%s" % (
            server[0],
            CONF.xenserver.connection_username,
            CONF.xenserver.connection_password,
            server[1],
            vm_uuid))
        return xml.read()
    except __HOLE__:
        LOG.exception(_LE('Unable to obtain RRD XML for VM %(vm_uuid)s with '
                          'server details: %(server)s.'),
                      {'vm_uuid': vm_uuid, 'server': server})
        return None
dataset/ETHPy150Open BU-NU-CLOUD-SP16/Trusted-Platform-Module-nova/nova/virt/xenapi/vm_utils.py/_get_rrd