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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _serve_image_metadata(self, request):
 """Given a tag and list of runs, serve a list of metadata for images. Note that the images themselves are not sent; instead, we respond with URLs to the images. The frontend should treat these URLs as opaque and should not try to parse information about them or generate them itself, as the format may change. Args: request: A werkzeug.wrappers.Request object. Returns: A werkzeug.Response application. """

    tag = request.args.get('tag')
    run = request.args.get('run')
    sample = int(request.args.get('sample', 0))
    response = self._image_response_for_run(run, tag, sample)
    return http_util.Respond(request, response, 'application/json')