Merging text files / How do I concatenate text files in Python?

merge.py

import shutil
import os
import glob

filenames = glob.glob('*.txt')

with open('output_file.txt','wb') as wfd:
    for f in filenames:
        with open(f,'rb') as fd:
            shutil.copyfileobj(fd, wfd)
            

merge3.py

import fileinput
import glob
import os
import re
 
def read_files(file_path):
 
    with open(file_path, encoding='utf8') as f:
        text = f.read()
        return text
 
def read_files(text, file_path):
 
    with open(file_path, 'rb') as f:
        f.write(text.encode('utf8', 'ignore'))
        
     
read_files = sorted(glob.glob("c:\\Folder6\\translated\\*.txt"))

with open("c:\\Folder6\\translated\\merged.txt", "wb") as outfile:
    for f in read_files:
        with open(f, "rb") as infile:
            outfile.write(infile.read())
            outfile.write(b"\n\n")

            
        fileinput.close()
        print(f)

merge_2.py

import glob2

filenames = glob2.glob('*.txt')  # list of all .txt files in the directory

with open('outfile.txt', 'w') as f:
    for file in filenames:
        with open(file) as infile:
            f.write(infile.read()+'\n')

import fileinput
import glob
with open('c:\\Folder6\\merged.txt', 'w') as f:
    for line in fileinput.input(glob.glob('c:\\Folder6\\*.txt')):
        f.write(line)
    fileinput.close()