display names of arguments, simplifying the process without requiring
additional configuration.
As such, you do not need to specify the dest_ and metavar_ parameters.
-The dest_ parameter defaults to the argument name with underscores ``_``
-replacing hyphens ``-`` . The metavar_ parameter defaults to the
-upper-cased name. For example::
+For optional arguments, the dest_ parameter defaults to the argument name, with
+underscores ``_`` replacing hyphens ``-``. The metavar_ parameter defaults to
+the upper-cased name. For example::
>>> parser = argparse.ArgumentParser(prog='PROG')
>>> parser.add_argument('--foo-bar')