def _perform(self, logfile, cookiefile, filename):
        """Simple perform to get a single request.
        """
        if filename == None:
            savefile = open(filename, "w")
        else:
            savefile = None
        c, resp = self.get_requester()
        if cookiefile:
            c.setopt(pycurl.COOKIEJAR, cookiefile) # write any cookies here
        else:
            # needed to enable cookie handling
            c.setopt(pycurl.COOKIEJAR, "/dev/null")
        if logfile is not None:
            logfile.write(self.__str__())
            logfile.write("\n\n")
            resp.logfile = logfile
        if savefile is not None:
            resp.set_savefile(savefile)
        # The curl library takes control here.
        try:
            c.perform()
        except pycurl.error as e:
            resp.error = e
        resp.finalize(c)
        del resp.logfile
        if savefile is not None:
            savefile.close()
        return resp
dataset/ETHPy150Open kdart/pycopia/WWW/pycopia/WWW/client.py/HTTPRequest._perform/operator `is not` -> `==`