def maybe_fileno(f):
    'Get object fileno, or :const:`None` if not defined.'
    try:
        return fileno(f)
    except FILENO_ERRORS:
        pass
Get object fileno, or :const:`None` if not defined.
def maybe_fileno(f):
    
    try:
        return fileno(f)
    except FILENO_ERRORS:
        pass