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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 make_cancel_request(repo_name, request_id, auth, dry_run=True):
 """ Cancel a request using buildapi self-serve. Returns a request. Buildapi documentation: DELETE /self-serve/{branch}/request/{request_id} Cancel the given request """

    url = '{}/{}/request/{}'.format(SELF_SERVE, repo_name, request_id)

    if dry_run:
        LOG.info('We would make a DELETE request to %s.' % url)
        return None

    LOG.info("We're going to cancel the job at %s" % url)
    req = requests.delete(url, auth=auth, timeout=TCP_TIMEOUT)
    # TODO: add debug message with the canceled job_id URL. Find a way
    # to do that without doing an additional request.
    return req