In the python documentation section 14.3.2.6 (http://docs.python.org/ lib/optparse-generating-help.html) in the last line it is written
"options that have a default value can include %default in the help string--optparse will replace it with str() of the option's default value. If an option has no default value (or the default value is None), %default expands to none." However this is true only for python 2.4 and newer and not for older versions. Though the documentation for optparse (section 14.3, http://docs.python.org/lib/module-optparse.html) says that the module is new for python 2.3, in this version a help string (default value = intermediate) e.g. help="interaction mode: novice, intermediate, or expert [default: %default]" prints interaction mode: novice, intermediate, or expert [default: %default] and not: interaction mode: novice, intermediate, or expert [default: intermediate] Only in python 2.4 and newer do you see the help string print as interaction mode: novice, intermediate, or expert [default: intermediate] I think the documentation should be modified so that it is made clear that %default in the help string behaves as is claimed only in version 2.4 and higher. O.S. used is RHEL 9 -- http://mail.python.org/mailman/listinfo/python-list