我正在尝试学习python，我正在阅读“用python自动化无聊的东西”一书，我发现当我尝试使用ubuntu的'python hello.py'（python 2）执行下面的代码时，它会出错如果我使用'python3 hello.py'我根本没有问题。
我想了解为什么以及如果在较旧的python2中我必须在我的代码顶部显式“导入”任何内容才能使错误消失？另外如果python3包含一些“内置”导入的模块，我不需要再导入哪里可以找到它们的列表？
以下是代码：
# this program asks for my name and tells me the lenght of my name
print("Hello world!")
print('What is your name? ')
myName = input()
print('It is good to meet you, ' + myName)
print('The lenght of your name is: ')
print(len(myName))
print('What is your age? ')
myAge = input()
print('You will be ' + str(int(myAge) +1) + ' in a year.')
这是我观察到的：
xubuntu:~/Documents$ python hello.py
Hello world!
What is your name?
Test
Traceback (most recent call last):
File "hello.py", line 5, in <module>
myName = input()
File "<string>", line 1, in <module>
NameError: name 'Giovanni' is not defined
xubuntu:~/Documents$ python3 hello.py
Hello world!
What is your name?
Test
It is good to meet you, Test
The lenght of your name is:
4
What is your age?
22
You will be 22 in a year.
感谢您帮助淘汰了一个菜鸟：）