Write a function called count_characters() that counts the number of times each character appears in a user-supplied string s. Your function should loop over each element of the string, and sequentually update a dict whose keys are characters and whose values are the number of occurrences seen so far. You may know of other ways to achieve the same result. However, you should use the loop approach, since this will generalize to the next exercise. Note: while the construct for Letter in s: will work for this exercise, it will not generalize to the next one. Use for i in range(Len(s)): instead. Example usage: count_characters ("tortoise") {'t': 2, 'o' : 2, 'r': 1, 'i': 1, 's': 1, 'e': 1} Hint Yes, you did a problem very similar to this one on HW1. Your Solution ]: # write count_characters() here Exercise 2 An n -gram is a sequence of n letters. For example, bol and old are the two 3-grams that occur in the string bold. Write a function called unt_ngrams that counts the number of times each n-gram occurs in a string, with n specified value n = 1 . You should be able to do this by making only a small modification to count_characters(). the user and with default Example usage: count_ngrams ("tortoise", n = 2) {'to': 2, 'or': 1, 'rt': 1, 'oi': 1, 'is': 1, 'se': 1} # output Your Solution ]: # write count_ngrams() here