human
Solve the following python programming problem given the following code:
def AddResponse(self, throttle_name, res) : 
    'Add to bandwidth throttle for given response.

    Args:
      throttle_name: The name of the bandwidth throttle to add to.
      res: The response whose size will be added to the throttle.
    ' 
    content = res.read () 
    def ReturnContent() : 
        return content 
res.read = ReturnContent 
    size = len (key) 
    headers = res.info () 
    for (key, value) in headers.items () : 
        size += len (('%s: %s
' % (key, value))) 
self.throttle.AddTransfer (throttle_name, size) 

    
    

    Fix the buggy line: size = len (key)
assistant
#Here is Python program to fix the buggy line: size = len (key)
.

size = len (content)