two other counter methods worth mentioning are most_common(and subtract(the most common method takes positive integer argument that determines the number of most common elements to return elements are returned as list of (key ,valuetuples the subtract method works exactly like update except instead of adding valuesit subtracts themfor exampleordered dictionaries the important thing about ordered dictionaries is that they remember the insertion orderso when we iterate over themthey return values in the order they were inserted this is in contrast to normal dictionarywhere the order is arbitrary when we test to see whether two dictionaries are equalthis equality is only based on their keys and valueshoweverwith an ordereddictthe insertion order is also considered an equality test between two ordereddicts with the same keys and values but different insertion order will return falsesimilarlywhen we add values from list using updatethe ordereddict will retain the same order as the list this is the order that is returned when we iterate the valuesfor example