Why does redhat-upgrade-tool throws error "TypeError: __new__() takes exactly 7 arguments (5 given)" ?

Issue

• While using the redhat-upgrade-tool command, getting traceback

# redhat-upgrade-tool --iso /test/rhel-server-7.2-x86_64-dvd.iso
Traceback (most recent call last):
  File "/usr/bin/redhat-upgrade-tool", line 450, in <module>
    args = parse_args()
  File "/usr/lib/python2.6/site-packages/redhat_upgrade_tool/commandline.py", line 123, in parse_args
    args, _leftover = p.parse_args()
  File "/usr/lib64/python2.6/optparse.py", line 1394, in parse_args
    stop = self._process_args(largs, rargs, values)
  File "/usr/lib64/python2.6/optparse.py", line 1434, in _process_args
    self._process_long_opt(rargs, values)
  File "/usr/lib64/python2.6/optparse.py", line 1509, in _process_long_opt
    option.process(opt, value, values, self)
  File "/usr/lib64/python2.6/optparse.py", line 782, in process
    value = self.convert_value(opt, value)
  File "/usr/lib64/python2.6/optparse.py", line 774, in convert_value
    return self.check_value(opt, value)
  File "/usr/lib64/python2.6/optparse.py", line 769, in check_value
    return checker(self, opt, value)
  File "/usr/lib/python2.6/site-packages/redhat_upgrade_tool/commandline.py", line 195, in isofile
    if any(value.startswith(d.mnt) for d in media.removable()):
  File "/usr/lib/python2.6/site-packages/redhat_upgrade_tool/commandline.py", line 195, in <genexpr>
    if any(value.startswith(d.mnt) for d in media.removable()):
  File "/usr/lib/python2.6/site-packages/redhat_upgrade_tool/media.py", line 76, in removable
    if not any(m.mnt == d.mnt for d in mounts("/etc/fstab")):
  File "/usr/lib/python2.6/site-packages/redhat_upgrade_tool/media.py", line 76, in <genexpr>
    if not any(m.mnt == d.mnt for d in mounts("/etc/fstab")):
  File "/usr/lib/python2.6/site-packages/redhat_upgrade_tool/media.py", line 44, in mounts
    yield FstabEntry(*line.split())
TypeError: __new__() takes exactly 7 arguments (5 given)