def METHOD_NAME(self, force=False):
    """Calculate the total number of downloads for the package"""
    if len(self._downloads) == 0 or force:
        for release in self.releases:
            urls = self.proxy.release_urls(self.package_name, release)
            self._downloads[release] = 0
            for url in urls:
                # upload times
                uptime = url['upload_time']
                if self.first_upload is None or uptime < self.first_upload:
                    self.first_upload = uptime
                    self.first_upload_rel = release
                if self.last_upload is None or uptime > self.last_upload:
                    self.last_upload = uptime
                    self.last_upload_rel = release
                self._downloads[release] += url['downloads']
    return self._downloads