Homework 10: Dictionaries

Write two functions:

1. The first function, vowel_histogram(s: str) -> Dict[str,int], should return a dictionary where the keys are vowels (a, e, i, o, u) and the values are the number of occurrences of each vowel in the string. Here is an example of calling the function in the console:

>>> vowel_histogram('This restaurant is a long way from our house.')
{'a': 4, 'e': 2, 'i': 2, 'o': 4, 'u': 3}

1. The second function, min_key(d: Dict[str, int]) -> str, should return the key in the dictionary with the smallest value. Here is an example of calling the function in the console:

>>> min_key({'a': 4, 'b': -5, 'c': 2, 'd': -7, 'e': 4})
'd'