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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 hash(self, value):
 """ Generate a hash of the given iterable. This is for use in a cache key. """

        if is_iterable(value):
            value = tuple(to_bytestring(v) for v in value)
        return hashlib.md5(six.b(':').join(value)).hexdigest()