This means that there is only one _I in the File menu.
<child>
<object class="GtkAction" id="file_import">
<property name="name">file_import</property>
<child>
<object class="GtkAction" id="file_import">
<property name="name">file_import</property>
- <property name="label" translatable="yes">_Import Data...</property>
+ <property name="label" translatable="yes">I_mport Data...</property>
<property name="stock-id">gtk-convert</property>
</object>
</child>
<property name="stock-id">gtk-convert</property>
</object>
</child>