Combining several PDFs into a single one

I have created some pdfs through a stand alone script, but would like to be able to create one single pdf file and not 100+ single page pdf files.

My naming convention has a different name for Left and Right pages.

Left: North_x_FAC
Right: North _x_SLD

Is there a way to get python to combine the files so that the single pdf file would have to correct ordering. North_1_FAC would come before North_1_SLD, and so on down to like 50+ pages of both left and right pages.