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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 chunk(url):
 """ create filesystem-safe places for url-keyed data to be stored """

    chunks = lambda l, n: [l[x: x+n] for x in xrange(0, len(l), n)]
    url_64 = base64.urlsafe_b64encode(url)
    return chunks(url_64, 255)