Python_ Foundation _01

1. Interpreter Path

#!/usr/bin/env python

2. Encoding

#-*-Coding:utf8-*-

1.ascill---00000000 (8-bit representation)

Disadvantage: Cannot express English

2.unicode---0000000000000000+ (at least 16 digits)

Disadvantage: Memory consumption, when the expression bit does not need more than 16 bits, causing excess memory consumption

1. 3.utf-8---How much to use is to express

　　Python3 no concern

Python2 each file appears in Chinese, the head must be added

3. Variable name　　

-Alphabet
-Digital
-Underline

Three-element constituent variables

• Cannot start with a letter
• cannot be a keyword (' and ', ' as ', ' assert ', ' Break ', ' class ', ' Continue ', ' Def ', ' del ', ' elif ', ' Else ', ' except ', ' exec ', ' finally ', ' For ', ' from ', ' global ', ' if ', ' import ', ' in ', ' was ', ' lambda ', ' not ', ' or ', ' pass ', ' print ', ' raise ', ' return ', ' Try ', ' W ' Hile ', ' with ', ' yield ')
• It's best not to repeat with Python's built-in function name

4. Recommended Programming Software

　　Pycharm

Python_ Foundation _01