python bug - pycurl lose string data of callback return

"""i used this code for get http data from web using pycurl

but, when i use bellow code "before" it get code loss partially(front of data).

I think when use undefined variable it makes data lose

then, use object "StringIO" it covered range of buffer to get data from web""" 

 

Import 

from StringIO import StringIO
import pycurl

 

before:

def http_body_callback(buf):
        contents = buf;
 
curl_handle.setopt(curl_handle.WRITEFUNCTION, self.http_body_callback);
curl_handle.perform();
 
print contents;

 

 

modify to:

storage = StringIO()
curl_handle.setopt(curl_handle.WRITEFUNCTION, storage.write);
curl_handle.perform();
 
print storage.getvalue()