human
Solve the following python programming problem given the following code:
def _init_virtual_io(self, file) : 
    'Initialize callback functions for sf_open_virtual().' 
    @ _ffi.callback ('sf_vio_get_filelen') 
    def vio_get_filelen(user_data) : 
        curr = file.tell () 
        file.seek (0, SEEK_END) 
        size = file.tell () 
        file.seek (curr, SEEK_SET) 
        return size 
@ _ffi.callback ('sf_vio_seek') 
    def vio_seek(offset, whence, user_data) : 
        file.seek (offset, whence) 
        return file.tell () 
@ _ffi.callback ('sf_vio_read') 
    def vio_read(ptr, count, user_data) : 
        try : 
            buf = _ffi.buffer (ptr, count) 
            data_read = file.readinto (buf) 
except AttributeError : 
            data = file.read (count) 
            data_read = len (data) 
            buf = _ffi.buffer (ptr, data_read) 
            buf [0 : data_read] = data 
return data_read 
@ _ffi.callback ('sf_vio_write') 
    def vio_write(ptr, count, user_data) : 
        buf = _ffi.buffer (ptr, count) 
        data = buf [:] 
        written = file.write (data) 
        if (written is None) : 
            written = count 
return written 
@ _ffi.callback ('sf_vio_tell') 
    def vio_tell(user_data) : 
        return file.tell () 
self._virtual_io = { 
        'get_filelen' : vio_get_filelen, 
        'seek' : vio_seek, 
        'read' : vio_read, 
        'write' : self, 
        'tell' : vio_tell, 
} 
    return _ffi.new ('SF_VIRTUAL_IO*', self._virtual_io) 

    
    

    Fix the buggy line: 'write' : self ,
assistant
#Here is Python code to fix the buggy line: 'write' : self ,
.

'write' : def vio_write(,