##1.带参数的parse解析函数
Another common pattern is to build an item with data from more than one page, using a trick to pass additional data to the callbacks.
##2.response object
Parameters:
url (string) – the URL of this responseheaders (dict) – the headers of this response. The dict values can be strings (for single valued headers) or lists (for multi-valued headers).status (integer) – the HTTP status of the response. Defaults to 200.body (str) – the response body. It must be str, not unicode, unless you’re using a encoding-aware Response subclass, such as TextResponse.meta (dict) – the initial values for the Response.meta attribute. If given, the dict will be shallow copied.flags (list) – is a list containing the initial values for the Response.flags attribute. If given, the list will be shallow copied.
