Append contacts to contactGroups from csv

[Esteban Mirizio]

Hi ! Im new over here. im working with nconf and i wonder how can i append contacts to a contactGroup using the importing from a csv file. At the moment every contact has added to one contactGroup, but i need append that contacs to another contactGroups, i have a list that matches the 'contact' with multiple 'contactGroups'.
Ej.

Contact ContactGroup
John Admin,normalUser,tecnicalUser
Mark normalUser,Admin

Thanks, hope u can help me