fix segmentation fault on clicking red point in compilation console if that compilation error coverts several units in plcopen file
closes #11
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<Python xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.w3.org/2001/XMLSchema" xsi:schemaLocation="python_xsd.xsd">
<![CDATA[]]>
</Python>