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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 lookup(dic, key, *keys):
 """A generic dictionary access helper. This helps simplify code that uses heavily nested dictionaries. It will return None if any of the keys in *keys do not exist. :: nested None """

    if keys:
        return lookup(dic.get(key, {}), keys[0], *keys[1:])
    return dic.get(key)