You haven't defined what it means to perform the == operator (whose function name is eq) on instances of your class.
Did you instead mean to compare parts of the properties of your objects? For instance did you want to compare part or all of the data property of your objects?
if(obj2.data(i) == obj1.data)
Though for that you'd probably want to ask if any of the elements in obj1.data matched.
if any(obj2.data(i) == obj1.data)