Performance Optimization is required

I require a performance optimization for my code. Below is the gist link
https://gist.github.com/moodleexpert/756d33613d08fc8581bce1bb4e806f21

As I have a file size of 2.5GB. I processing it locally, but it is taking too much time. Same thing I am doing with a bash script it processes the data within 5 mins. Can tell me what exactly I am doing wrong
