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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 ThreadsWithRunningExecServers(self):
 """Returns a list of tids of inferior threads with open exec servers."""

    socket_dir = '/tmp/pyringe_%s' % self.inferior.pid
    if os.path.isdir(socket_dir):
      return [int(fname[:-9])
              for fname in os.listdir(socket_dir)
              if fname.endswith('.execsock')]
    return []