What are the names of the different customers who have taken out a loan, ordered by the total amount that they have taken?
return customers ;return loans taken  out by #1 ;return number of  #2 for each #1 ;return #1 where #3 is  at least one ;return loans taken  out by #4 ;return amounts of #5 ;return the   sum of #6 for each #4 ;return the   names of #4 ;return #8 sorted by #7
['select', 'project', 'group', 'comparative', 'project', 'project', 'group', 'project', 'sort']