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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_session(scraper):
 """ Instantiate a session with the desired configuration parameters, including the cache policy. """

    cache_path = os.path.join(scraper.config.data_path, 'cache')
    cache_policy = scraper.config.cache_policy
    cache_policy = cache_policy.lower().strip()
    session = ScraperSession()
    session.scraper = scraper
    session.cache_policy = cache_policy

    adapter = CacheControlAdapter(
        FileCache(cache_path),
        cache_etags=True,
        controller_class=PolicyCacheController
    )
    session.mount('http://', adapter)
    session.mount('https://', adapter)
    return session