'Set ``tag_sets`` to a list of dictionaries like [{\'dc\': \'ny\'}] to
read only from members whose ``dc`` tag has the value ``"ny"``.
To specify a priority-order for tag sets, provide a list of
tag sets: ``[{\'dc\': \'ny\'}, {\'dc\': \'la\'}, {}]``. A final, empty tag
set, ``{}``, means "read from any member that matches the mode,
ignoring tags." MongoReplicaSetClient tries each set of tags in turn
until it finds a set of tags with at least one matching member.
.. seealso:: `Data-Center Awareness
<http://www.mongodb.org/display/DOCS/Data+Center+Awareness>`_'

@property
def tag_sets(self):

    return (list(self.__tag_sets) if self.__tag_sets else [{}])
