Optimzed tracing of STRING type variables value. Now, only used size is transfered in debug buffer.
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<Python xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.w3.org/2001/XMLSchema" xsi:schemaLocation="python_xsd.xsd">
<![CDATA[]]>
</Python>