code: def get_njobs_in_queue(self, username=None):
          
          if username is None: username = getpass.getuser()
          njobs, process = self._get_njobs_in_queue(username=username)
  
          if process is not None and process.returncode != 0:
              # there's a problem talking to squeue server?
              err_msg = ('Error trying to get the number of jobs in the queue' +
                         'The error response reads:\n {}'.format(process.stderr.read()))
              logger.critical(err_msg)
  
          if not isinstance(self, ShellAdapter):
              logger.info('The number of jobs currently in the queue is: {}'.format(njobs))
  
          return njobs
docs: returns the number of jobs in the queue, probably using subprocess or shutil to
          call a command like 'qstat'. returns None when the number of jobs cannot be determined.
  
          Args:
              username: (str) the username of the jobs to count (default is to autodetect)