How to merge many pdf at once with python

With this code you can merge all the file in the current directory.

from glob import glob
from PyPDF2 import PdfFileMerger
import os


def pdf_merge(name):
    ''' Merges all the pdf files in current directory '''
    filename = f"{name}.pdf" # add extension to name
    merger = PdfFileMerger()
    allpdfs = [a for a in glob("*.pdf")]
    [merger.append(pdf) for pdf in allpdfs]
    with open(filename, "wb") as new_file:
        merger.write(new_file)
    os.system(f"start {filename}") # opens the file


if __name__ == "__main__":
    pdf_merge(input("Output file name: "))