Description of variable composition
Variable name assignment symbol (=) variable values
Brief variable naming names
1. Variable names need to have real meaning
2. a combination of numbers, letters or underscore named variables, not the beginning of a digital
3. You can not use the keyword name
Function of the comments
1. Let the code behind the failure, so that the python interpreter will not explain it, as ordinary characters
2. The programmer can add the interpretation of the code behind the front, to facilitate the understanding of the code
Use turtle construct a picture library, attached to the markdown document
