question: Find the the names of the tourist attractions that the tourist named Alison visited but Rosalind did not visit.
#1 return tourist  attractions 
#2 return tourists that  visited #1 
#3 return #1 where  #2 is  Alison 
#4 return #1 where  #2 is  Rosalind 
#5 return #3 besides #4 
#6 return names of  #5