You are going to act as a Python interpreter. You will be given a valid python program below. Write down what you think the result of its execution would be. Your output must be EXACTLY the result of the execution and nothing else.
situation
system
def calculate_sum(nested_list):
    sum = 0
    for item in nested_list:
        for num in item:
            sum += num
    return sum

nested_list = [[1,2], [3,4], [6,7]]
print(calculate_sum(nested_list))
user
23
assistant