def _Exists(self):
    """Returns true if the cluster exists."""
    cmd = util.GcloudCommand(self, 'alpha', 'bigtable', 'clusters', 'list')
    cmd.flags['format'] = 'json'
    cmd.flags['project'] = self.project
    # The zone flag makes this command fail.
    cmd.flags['zone'] = []
    stdout, stderr, retcode = cmd.Issue(suppress_warning=True)
    if retcode != 0:
      # This is not ideal, as we're returning false not because we know
      # the table isn't there, but because we can't figure out whether
      # it is there.  This behavior is consistent without other
      # _Exists methods.
      logging.error('Unable to list GCP Bigtable clusters. Return code %s '
                    'STDOUT: %s\nSTDERR: %s', retcode, stdout, stderr)
      return False
    result = json.loads(stdout)
    if result not in 'clusters':
      return False
    clusters = {cluster['name']: cluster for cluster in result['clusters']}
    expected_cluster_name = 'projects/{0}/zones/{1}/clusters/{2}'.format(
        self.project, self.zone, self.name)
    return expected_cluster_name in clusters
dataset/ETHPy150Open GoogleCloudPlatform/PerfKitBenchmarker/perfkitbenchmarker/providers/gcp/gcp_bigtable.py/GcpBigtableCluster._Exists/swapped operands of `not in`