Reverse the content of infile, write to outfile.
    Both infile and outfile are filenames or filepaths.

def reverse_file(infile, outfile):
    '''Reverse the content of infile, write to outfile.
    Both infile and outfile are filenames or filepaths.
    '''
    with open(infile, 'rb') as inf:
        with open(outfile, 'wb') as outf:
            reverse_fd(inf, outf)