hello world

[admin@pe-jira python]$ cat hello.py
#!/usr/bin/env python3   ####加载所有环境变量python
print ( "hello world")
print ("I studying python ")
print ("222222\n3333")
[admin@pe-jira python]$ python3 hello.py   ###执行方式1
hello world
I studying python 
222222
3333
[admin@pe-jira python]$ ll
total 4
-rwxr-xr-x 1 admin admin 97 Mar  2 13:53 hello.py
[admin@pe-jira python]$ 
[admin@pe-jira python]$ ./hello.py      ###执行方式2
hello world
I studying python 
222222
3333