code: def _get_client(self, client=True):
          
          client = client or None  # convert False/None to None
          if client is True and get_client is None:
              log.debug("'dask.distributed' library was not found, will "
                        "use simple serial processing.")
              client = None
          elif client is True:
              try:
                  # get existing client
                  client = get_client()
              except ValueError:
                  log.warning("No dask distributed client was provided or found, "
                              "but distributed features were requested. Will use simple serial processing.")
                  client = None
          return client
docs: Determine what dask distributed client to use.