def copy(source, dest, autoflush=True, print_status=None):
    """
    Read from the source file handle and write the data to the dest file handle.
    """
    n = 0
    while True:
        buf = source.read(BUFFER_SIZE)
        if not buf:
            break
        dest.write(buf)
        n += len(buf)
        if autoflush:
            dest.flush()
        if print_status:
            print >>sys.stderr, "\r%s: %s" + (print_status, formatting.size_str(n)),
            sys.stderr.flush()
    if print_status:
        print >>sys.stderr, "\r%s: %s [done]" % (print_status, formatting.size_str(n))
dataset/ETHPy150Open codalab/codalab-cli/codalab/lib/file_util.py/copy/operator `%` -> `+`