my_set = set()
print(my_set)

my_set.add(1)
print(my_set)

my_set.add(2)
print(my_set)

my_set.add(2)
print(my_set)

# have to be unique value
# the same value cannot be added twice
my_set2 = set()
my_set2.add('mississippi')
print(my_set2)


