'Retrieve an Organization Release\'s File
Return details on an individual file within a release.  This does
not actually return the contents of the file, just the associated
metadata.
:pparam string organization_slug: the slug of the organization the
release belongs to.
:pparam string version: the version identifier of the release.
:pparam string file_id: the ID of the file to retrieve.
:auth: required'

def get(self, request, organization, version, file_id):

    try:
        release = Release.objects.get(organization_id=organization.id, version=version)
    except Release.DoesNotExist:
        raise ResourceDoesNotExist
    if (not self.has_release_permission(request, organization, release)):
        raise PermissionDenied
    try:
        releasefile = ReleaseFile.objects.get(release=release, id=file_id)
    except ReleaseFile.DoesNotExist:
        raise ResourceDoesNotExist
    download_requested = (request.GET.get('download') is not None)
    if (download_requested and request.access.has_scope('project:write')):
        return self.download(releasefile)
    elif download_requested:
        return Response(status=403)
    return Response(serialize(releasefile, request.user))
