Python Notes

1."Ryan".lower() which will return "ryan".

2. print "The %s who %s %s!" % ("Knights","say","Ni")

prints "The Knights who say Ni!"

3. Boolean operators aren't just evaluated from left to right. Just like with arithmetic operators, there's an order of operations for boolean operators:

1. not is evaluated first;
2. and is evaluated next;
3. or is evaluated last.

For example, True or not False andFalse returns True.

4. String.isalpha()

5. an empty list is just []

6.

if x not in range(8) or \   y not in range(3):        print "Outside the range"

The example above checks if either x ory are outside those ranges. The\ character just continues theif statement onto the next line.

7. "UnicodeEncodeError: ‘ascii’ codec can’t encode characters in position xxx ordinal not in .."

    import sys      reload(sys)      sys.setdefaultencoding('utf8')   

8. 执行系统命令

import osprint os.system('ping www.pythontab.com')

9.ImportError: cannot import name Flask

文件名不要和模块重复(flask.py)