Variable product problem

Hello,
I’ve got problem with importing product from XML file.
I want to create products with size variations.
The XML file is:

</description_long>
<sizechart>58</sizechart>
<variants>
<variant code="2016101243060" size="86"/>
<variant code="2016101243077" size="92"/>
<variant code="2016101243084" size="98"/>
<variant code="2016101243091" size="104"/>
</variants>
<pictures>
<picture>

I do not have an idea how to import SIZES from this kind of file.

Thajnk you for help