Off topic:concatenate all my fasta files in a directory into one file with Python

Question

[benjamin]

Hi all, I actually have to cat all my fasta files into directory but with python. In bash command it would be:

cat ./* > newfile

I guess it should be something like that:

with open(new_directory_0035+"/merged.txt", 'w') as f:
    for line in fileinput.input(glob.glob(new_directory_0035+"/*")):
        f.write(line)
    fileinput.close()

but it is still running after 20 minutes, do you know if I wrote something wrong? And it seems to take to much memory as well... Thanks