reverse keyword in python code example

Example 1: how to reverse a dictionary in python

def inverse_dict(my_dict):
    """
    the func get a dictinary and reverse it, the keys become values and the values become keys.
    :param my_dict: the dictinary that need to be reversed.
    :return: a VERY pretty dictionary.
    """
    result_dict = {}
    for key, value in my_dict.items():
        if not value in result_dict.keys():
            result_dict[value] = []
        result_dict[value].append(key)
    return result_dict, print(result_dict)

Example 2: reverse python3

arr = [2,5,32,86,4,131,97]

# reverse without modifying input, using range:
for i in range(len(arr)-1, -1, -1):
    print(arr[i])
    
# reverse and modifying input:
arr.reverse()