def write(self, data, *, mode=None, buffering=-1, encoding=None, newline=None):
        ''' write data into the file. '''
        if mode is None:
            mode = 'w' if isinstance(data, str) else 'wb'
        with self.open(mode=mode, buffering=buffering, encoding=encoding, newline=newline) as fp:
            return fp.write(data)
write data into the file.