Comma errors while using vim-syntastic plugin

When saving python files, vim-syntactic starts debugging and raises syntax errors (specifically commas), whether its in a list, dictionary, tuple etc. Here is an image after saving python file.

Vim-Syntactic throws syntax errors when you don't add a space after commas.

√ animals = set(['cat', 'dog', 'mouse'])  # no errors
x animals = set(['cat','dog','mouse'])  # errors