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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 observe(self, key, master_only=False):
 """Return storage information for a key. It returns a :class:`.ValueResult` object with the ``value`` field set to a list of :class:`~.ObserveInfo` objects. Each element in the list responds to the storage status for the key on the given node. The length of the list (and thus the number of :class:`~.ObserveInfo` objects) are equal to the number of online replicas plus the master for the given key. :param string key: The key to inspect :param bool master_only: Whether to only retrieve information from the master node. .. seealso:: :ref:`observe_info` """

        return _Base.observe(self, key, master_only=master_only)