Frame not found by LoadFrame

Hi,
the following test program fails with the error

Error: XRC resource 'frame_1' (class 'wxFrame') not found!

Thanks for any help,
Fabrizio


test program (python 2.7.6, wxpy 2.8.12.1)
-----------------

from wx import xrc

xml_resource = xrc.XmlResource('test.wxg')
root = xml_resource.LoadFrame(None,'frame_1')


test.wxg
-----------

<?xml version="1.0"?>
<!-- generated by wxGlade 0.6.8 on Thu Mar  5 18:07:57 2015 -->

<application path="/home/fabrizio/avc/tmp/tmp.py" name="" class=""
option="0" lan
guage="python" top_window="frame_1" encoding="UTF-8" use_gettext="1"
overwrite="1
" use_new_namespace="1" for_version="2.8" is_template="0"
indent_amount="4" inden
t_symbol="space" source_extension=".cpp" header_extension=".h">
    <object class="wxFrame" name="frame_1" base="EditFrame">
        <style>wxDEFAULT_FRAME_STYLE</style>
        <title>frame_1</title>
        <object class="wxBoxSizer" name="sizer_1" base="EditBoxSizer">
            <orient>wxVERTICAL</orient>
            <object class="sizerslot" />
        </object>
    </object>
</application>

====


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