First solution in Clear category for Non-unique Elements by
#Your optional code here
#You can import some modules or create additional functions
#Your code here
#It's main function. Don't remove this function
#It's used for auto-testing and must return a result for check.
#replace this for solution
return [b for b in data if data.count(b) > 1]
#You can use list.count(element) method for counting.
#Create new list with non-unique elements
#or remove elements from original list (but it's bad practice for many real cases)
#Loop over original list
May 8, 2014