====== TradingPartnerGLN ======

This function gets the location backend reference as the first argument and returns the stored GLN of the respective trading partner location. \\\ 

==== Syntax: ====

<code>TradingPartnerGLN('BackendReference')</code>

==== Sample: ====

<code>TradingPartnerGLN('7001419')</code>
return e.g.: 4035811991014