Find the last name of female (sex is F) students in the descending order of age.
return students ;return sex of  #1 ;return #1 where  #2 is  female ;return ages of  #3 ;return last names of  #3 ;return #5 sorted by #4 in descending order
['select', 'project', 'comparative', 'project', 'project', 'sort']