Zend certified PHP/Magento developer

magento2 why added automatically on getchildhtml()

I am calling getChildHtml() function on calling block html in my template, It was returning me only the content of the block which is saved in magento backend block section, i have imported them from demo.
Its all going will, until i made changes to content in backend and saved. Now, Not not only html of the block in returning in getChildHmtl() function call, but it is now encircled with this div below

<div data-content-type="html" data-appearance="default" data-element="main" data-decoded="true">
 block html goes here.
</div>

Why this returned like this now after saving block in magento backedend? one reason may be this advanced setting saved first time, what do you think, i want to get rid of this uppper div
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