Yum fails with "AttributeError: 'RhnRepo' object has no attribute '_retry_no_cache'" on system registered with Red Hat Satellite 5.x.

Issue

• All yum commands fails with below error on Red Hat Enterprise Linux 7 registered with Satellite-5x:

# yum repolist
Loaded plugins: rhnplugin, search-disabled-repos
This system is receiving updates from RHN Classic or Red Hat Satellite.
Traceback (most recent call last):
  File "/usr/bin/yum", line 29, in <module>
    yummain.user_main(sys.argv[1:], exit_code=True)
  File "/usr/share/yum-cli/yummain.py", line 365, in user_main
    errcode = main(args)
  File "/usr/share/yum-cli/yummain.py", line 174, in main
    result, resultmsgs = base.doCommands()
  File "/usr/share/yum-cli/cli.py", line 573, in doCommands
    return self.yum_cli_commands[self.basecmd].doCommand(self, self.basecmd, self.extcmds)
  File "/usr/share/yum-cli/yumcommands.py", line 2149, in doCommand
    base.repos.populateSack()
  File "/usr/lib/python2.7/site-packages/yum/repos.py", line 383, in populateSack
    sack.populate(repo, mdtype, callback, cacheonly)
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 224, in populate
    if self._check_db_version(repo, mydbtype):
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 316, in _check_db_version
    return repo._check_db_version(mdtype)
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1484, in _check_db_version
    repoXML = self.repoXML
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1670, in <lambda>
    repoXML = property(fget=lambda self: self._getRepoXML(),
  File "/usr/share/yum-plugins/rhnplugin.py", line 564, in _getRepoXML
    return YumRepository._getRepoXML(self)
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1666, in _getRepoXML
    self._loadRepoXML(text=self.ui_id)
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1657, in _loadRepoXML
    return self._groupLoadRepoXML(text, self._mdpolicy2mdtypes())
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1631, in _groupLoadRepoXML
    if self._commonLoadRepoXML(text):
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1456, in _commonLoadRepoXML
    result = self._getFileRepoXML(local, text)
  File "/usr/lib/python2.7/site-packages/yum/yumRepo.py", line 1234, in _getFileRepoXML
    size=102400) # setting max size as 100K
  File "/usr/share/yum-plugins/rhnplugin.py", line 376, in _getFile
    start, end, copy_local, checkfunc, text, reget, cache, size)
  File "/usr/share/yum-plugins/rhnplugin.py", line 480, in _noExceptionWrappingGet
    retry_no_cache=self._retry_no_cache
AttributeError: 'RhnRepo' object has no attribute '_retry_no_cache'