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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _build_query_url(self, page = None, verbose = False):
 """ builds the url to call """

        query = []
#        # build the filters
#        for afilter in self.filters.keys():
#            value = self.filters[afilter]
#            print"filter:%s value:%s" % (afilter,value)
#            value = urlencode(value)
#            query_str = u"%s=%s" % (afilter, value)
        if len(self.filters) > 0:
            query.append(urlencode(self.filters))
        if self.sort:
            query_str = u"%s=%s" % (u"sort", self.sort)
            query.append(query_str)
        if self.sort_by:
            query_str = u"%s=%s" % (u"sort_by", self.sort_by)
            query.append(query_str)
        if self.per_page:
            query_str = u"%s=%s" % (u"per_page", self.per_page)
            query.append(query_str)
        if page:
            query_str = u"%s=%s" % (u"page", page)
            query.append(query_str)
        query = u"?%s" % (u"&".join(query))
        url = u"%s%s" % (self.get_list_endpoint()['href'],query)
        url = u"%s%s%s" % (self.__api__.base_url, API_BASE_PATH, url)
        msg = "_build_query_url: url:%s" % url
        log.debug(msg)
        if verbose:
            print msg
        return url