写几个代码来看看

以下是一些示例代码：

1. 计算两个数字的和

num1 = 10
num2 = 20
sum = num1 + num2
print("The sum of", num1, "and", num2, "is", sum)

输出：

The sum of 10 and 20 is 30

2. 判断一个数字是否为偶数

num = 6
if num % 2 == 0:
    print(num, "is even")
else:
    print(num, "is odd")

输出：

6 is even

3. 遍历一个列表并打印每个元素

fruits = ["apple", "banana", "orange", "grape"]
for fruit in fruits:
    print(fruit)

输出：

apple
banana
orange
grape

4. 定义一个函数来计算一个数的平方

def square(num):
    return num ** 2

print(square(5))

输出：

25