Codecademy Python 3 Code Challenge: Unique Values

# Write your unique_values function here:
def unique_values(my_dictionary):
  empty_list = []

  for value in my_dictionary.values():
    if value not in empty_list:
      empty_list.append(value)

  return len(empty_list)

# Uncomment these function calls to test your  function:
print(unique_values({0:3, 1:1, 4:1, 5:3}))
# should print 2
print(unique_values({0:3, 1:3, 4:3, 5:3}))
# should print 1