human
Solve the following python programming problem given the following code:
@ patch.object (Collector, 'flush') 
def test_mbean_blacklisting(self, publish_mock) : 
    def se(url) : 
        if (url.find ('org.apache.cassandra.metrics') > 0) : 
            return self.getFixture ('metrics.json') 
else : 
            if (url.find ('list/org.apache.cassandra.db') > 0) : 
                return self.getFixture ('cas_db.json') 
else : 
                if (url.find ('org.apache.cassandra.db:type=StorageService') > 0) : 
                    return Exception ('storage service should be blacklisted') 
else : 
                    if (url.find ('list?ifModifiedSince') > 0) : 
                        return self.getFixture ('cas_list.json') 
else : 
                        return self.getFixture ('storage_proc.json') 
patch_urlopen = patch ('urllib2.urlopen', Mock (side_effect = self)) 
    self.collector.config ['mbean_blacklist'] = ['org.apache.cassandra.db:type=StorageService'] 
    with patch_urlopen : 
        self.collector.collect () 
metrics = find_metric (self.collector.payload, 'org.apache.cassandra.db.StorageProxy.cascontentiontimeout') 
    self.assertNotEqual (len (metrics), 0) 

    
    

    Fix the buggy line: patch_urlopen = patch ('urllib2.urlopen', Mock (side_effect = self))
assistant
#Here is Python code to find ('org.

patch_urlopen = patch ('urllib2.urlopen', Mock (side_effect = def se())