I would like to have a php-script that reades the "lng" and "lat" from the source of this link:

and produces a txt file like this:
-47.98731987077525, -15.81370208749796
-47.81370208749796, -13.81370208749796

In other words, it should search for the lng and lat, and find the numbers and then finally produce a file with longitude- and latitude numbers one each line