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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 _RunOsLoginNssCache(self):
 """Run the OS Login NSS cache binary. Returns: int, the return code from the call, or None if the script is not found. """

    try:
      return subprocess.call([constants.OSLOGIN_NSS_CACHE_SCRIPT])
    except OSError as e:
      if e.errno == errno.ENOENT:
        return None
      else:
        raise