loads a file into the defintion triplestore

        args:
            filepath: the path to the file

def load_file(self, filepath, **kwargs):
        """ loads a file into the defintion triplestore

        args:
            filepath: the path to the file
        """
        log.setLevel(kwargs.get("log_level", self.log_level))
        filename = os.path.split(filepath)[-1]
        if filename in self.loaded:
            if self.loaded_times.get(filename,
                    datetime.datetime(2001,1,1)).timestamp() \
                    < os.path.getmtime(filepath):
                self.drop_file(filename, **kwargs)
            else:
                return
        conn = self.__get_conn__(**kwargs)
        conn.load_data(graph=getattr(__NSM__.kdr, filename).clean_uri,
                       data=filepath,
                       # log_level=logging.DEBUG,
                       is_file=True)
        self.__update_time__(filename, **kwargs)
        log.warning("\n\tfile: '%s' loaded\n\tconn: '%s'\n\tpath: %s",
                    filename,
                    conn,
                    filepath)
        self.loaded.append(filename)