question: How long is the total lesson time took by customer with first name as Rylan and last name as Goodwin?
#1 return customers 
#2 return first names of #1 
#3 return last names of #1 
#4 return #1 where #2 is  Rylan 
#5 return #1 where #3 is  Goodwin 
#6 return #1 in both #4 and #5 
#7 return lessons that  #6 took 
#8 return times of #7 
#9 return sum of #8