ElasticSearch.search_simple(index,itype,key,search_term)
        Usage:
        > es = ElasticSearch()
        > es.search_simple('twitter','users','name','kim')

def search_simple(self, index,itype, key, search_term):
        '''
        ElasticSearch.search_simple(index,itype,key,search_term)
        Usage:
        > es = ElasticSearch()
        > es.search_simple('twitter','users','name','kim')
        '''
        request = self.session
        url = 'http://%s:%s/%s/%s/_search?q=%s:%s' % (self.host,self.port,index,itype,key,search_term)
        response = request.get(url)

        return response