When last_version is deleted, do not delete text and previous versions in cascade, but really delete text only when there is no previous version, otherwise update text.last_version with previous version.
<?xml version="1.0" encoding="UTF-8"?>
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<name>comt</name>
<comment></comment>
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<buildSpec>
<buildCommand>
<name>org.python.pydev.PyDevBuilder</name>
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<nature>org.python.pydev.pythonNature</nature>
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