Empty Dictionary: 
{}

Dictionary after adding 4 elements: 
{0: 'apple', 2: 'mango', 3: 'cat', 4: 'dog'}

Dictionary after adding 5 elements: 
{0: 'apple', 2: 'mango', 3: 'cat', 4: 'dog', 'Value_set': (2, 3, 4, 8)}