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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 _get_image_url(self, image_id):
 """Gets the url for the specified image. Unfortunatly this only works for images uploaded by the user. The images provided by google will not be found. :param str image_id: image identifier :return: str - api url of the image """

        gce = self._connect()
        filter = "name eq %s" % image_id
        request = gce.images().list(project=self._project_id, filter=filter)
        response = self._execute_request(request)
        response = self._wait_until_done(response)

        image_url = None
        if "items" in response:
            image_url = response["items"][0]["selfLink"]

        if image_url:
            return image_url
        else:
            raise ImageError("Could not find given image id `%s`" % image_id)