old_contents: # Set
  #Removes the duplicates from the given group of values to create the set.
  flight_set = {500,520,600,345,520,634,600,500,200,200}
  print("Flight Set : ", flight_set)
  
  # Converting List into Set
  passengers_list=["George", "Annie", "Jack", "Annie", "Henry", "Helen", "Maria", "George", "Jack", "Remo"]
  unique_passengers=set(passengers_list)#	set function - removes the duplicates from the list and returns a set
  
  print("Unique Passengers : ", unique_passengers)
new_contents: # Set
  #Removes the duplicates from the given group of values to create the set.
  flight_set = {500,520,600,345,520,634,600,500,200,200}
  print("Flight Set : ", flight_set)
  
  # Converting List into Set
  passengers_list=["George", "Annie", "Jack", "Annie", "Henry", "Helen", "Maria", "George", "Jack", "Remo"]
  unique_passengers=set(passengers_list)#	set function - removes the duplicates from the list and returns a set
  
  print("Unique Passengers : ", unique_passengers)
  
  # Set can also contain any data types, even tuples are also allowed.
  # Add function .add()
  unique_passengers.add("Robin")
  
  # .update() function works only for iterable objects
  unique_passengers.update(["Rahul", "Robin"])
  unique_passengers.update({"Kanvi", "Beatriz"})
  
  # Both the discard() and remove() functions take a single value as an argument and
  # removes that value from the set. If that value is not present, discard() does nothing,
  # but remove() will raise a KeyError exception.
  unique_passengers.discard("Annie")
  unique_passengers.remove("George")
  
  a = {2, 4, 5, 9}
  b = {2, 4, 11, 12}
  a.union(b) # Values which exist in a or b
  a.intersection(b) # Values which exist in a and b
  a.difference(b) # Values which exist in a but not in b
subject: Set with add, update, discard, remove, union, intersection, difference