英文文件：
input([prompt])
If the prompt argument is present, it is written to standard output without a trailing newline. The function then strping line inn read newline), and returns that. When EOF is read, EOFError is raised
說明：
1. 如果提供了promat參數，首先將參數值輸出到標準的輸出，並且不換行。函數讀取使用者輸入的值，將其轉換成字串。
>>> s = input('please input your name:') please input your name:Ain>>> s'Ain'
