add find_membership method
add find_membership method

Bastonis/HuddleUp,Revolaution/HuddleUp,Bastonis/HuddleUp,Revolaution/HuddleUp,Bastonis/HuddleUp,Bastonis/SquareUp,Bastonis/SquareUp,Revolaution/HuddleUp,Bastonis/SquareUp