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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 get(self, key):
 """Return a value from the container or None if the value is not set. :param key: a string using dotted notation for nested dictionary lookups """

        self.inspect_if_not_inspected()

        def get_value(dictionary, key):
            return (dictionary or {}).get(key)

        return reduce(get_value, key.split('.'), self.dictionary)