def METHOD_NAME(self, query_string, cursor, page_size):
    quoted = quote(query_string, safe="/")
    qsize = quote(str(page_size))
    qcursor = quote(str(cursor))
    if qsize is None or quoted is None or qcursor is None:
        raise EuropePMCException(None, "unable to url escape the string")
    url = app.config.get("EPMC_REST_API") + "search?query=" + query_string
    url += "&resulttype=core&format=json&pageSize=" + qsize
    if cursor != "":
        url += "&cursorMark=" + qcursor
    return url