Exchange 2013 CU2 Coexistence

Exchange 2013 Cu2 on Windows 2012 coexistence with Exchange 2007.

we are migrating mailboxes.

Question:

I have found a distribution group named " Exchange Users" which is having most of the exchange recepients as members.

I have checked exchange setup documents for particular distribution group creation not found anything related to the DL. 

Articles refered:

http://technet.microsoft.com/en-us/library/bb125224(v=exchg.150).aspx

http://technet.microsoft.com/en-us/library/bb691338(v=exchg.141).aspx

http://technet.microsoft.com/en-us/library/bb288907(v=exchg.80).aspx

I want to know the distribution group "exchange users" is it created by exchange setup?