Read csv file and create a new file

[io]

> Just use a tolower() method on both strings when you're comparing them.
>   Of course, that may not work well with international character sets.
> Some characters in some languages have no lowercase equivalent, and
> using toupper() has the same problem in other languages.
> 
> Also, the approach to case insensitive differs between Python 2.x and
> 3.x

Thanks for the info !
What about str().lower()?