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    Hello,<br>
    <br>
    in <br>
      <a class="moz-txt-link-freetext" href="http://docs.python.org/3.4/library/argparse.html#add-help">http://docs.python.org/3.4/library/argparse.html#add-help</a><br>
    <br>
    The last example reads:<br>
    <p>The help option is typically <tt class="docutils literal"><span
          class="pre">-h/--help</span></tt>. The exception to this is
      if the <tt class="docutils literal"><span class="pre">prefix_chars=</span></tt>
      is specified and does not include <tt class="docutils literal"><span
          class="pre">-</span></tt>, in
      which case <tt class="docutils literal"><span class="pre">-h</span></tt>
      and <tt class="docutils literal"><span class="pre">--help</span></tt>
      are not valid options. In
      this case, the first character in <tt class="docutils literal"><span
          class="pre">prefix_chars</span></tt> is used to prefix
      the help options:</p>
    <div style="position: relative;" class="highlight-python3">
      <div class="highlight"><span title="Hide the prompts and output"
          style="cursor: pointer; position: absolute; top: 0px; right:
          0px; border-color: rgb(170, 204, 153); border-style: solid;
          border-width: 1px; color: rgb(170, 204, 153); font-family:
          monospace; padding-left: 0.2em; padding-right: 0.2em;
          border-radius: 0px 3px 0px 0px; text-decoration: none;"
          class="copybutton">>>></span>
        <pre><span style="display: inline;" class="gp">>>> </span><span class="n">parser</span> <span class="o">=</span> <span class="n">argparse</span><span class="o">.</span><span class="n">ArgumentParser</span><span class="p">(</span><span class="n">prog</span><span class="o">=</span><span class="s">'PROG'</span><span class="p">,</span> <span class="n">prefix_chars</span><span class="o">=</span><span class="s">'+/'</span><span class="p">)</span>
<span style="display: inline;" class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">print_help</span><span class="p">()</span>
<span style="display: inline;" class="go">usage: PROG [-h]</span>

<span style="display: inline;" class="go">optional arguments:</span>
<span style="display: inline;" class="go">  -h, --help  show this help message and exit</span>
 </pre>
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    This example does not show the effect.<br>
    On my Ubuntu I get:<br>
    <pre>% python3.2
Python 3.2.3 (default, Apr 10 2013, 05:07:54) 
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import argparse
>>> parser = argparse.ArgumentParser(prog='PROG', prefix_chars='+/')
>>> parser.print_help()
usage: PROG [+h]

optional arguments:
  +h, ++help  show this help message and exit
>>> 

</pre>
    Docs of 2.7, 3.3 and 3.4 show this error, 3.2 is correct.<br>
    <br>
    Regards<br>
    <br>
    Patrick<br>
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