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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 install_cache(expire_after=12 * 3600, cache_post=False):
 """ Patches the requests library with requests_cache. """

    allowable_methods = ['GET']
    if cache_post:
        allowable_methods.append('POST')
    requests_cache.install_cache(
        expire_after=expire_after,
        allowable_methods=allowable_methods)