#my function

def sum_of_values(my_dict, a_list):

    total = 0

    for key in my_dict:

        if key in a_list:      #if the key in the dictionary is also in the list

            total += my_dict[key]  #this will keep on adding the target corresponding value of the key

    print(total)


my_dict = {"a": 5, "b": 3, "c": 10}  #sample dictionary


sum_of_values(my_dict, ["a", "c"])            #Example
sum_of_values(my_dict, ["a", "b", "c"])