Add extra detail
Fix missing commas and closing braces
Remove escaped quotes and external gist link
Merge pull request #650 from checkcheckzz/master

[json/cn]: fix the original typo
Update python3.html.markdown

fixed python 3 english sets error and editted .add comment because .add only accepts one argument
Merge pull request #653 from xksteven/master

[python 3/en] fixed error in sets
Merge pull request #643 from marcoms/patch-1

Add extra detail