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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 rcParams(self):
 """ Return rcParams dict for this theme. Notes ----- Subclasses should not need to override this method method as long as self._rcParams is constructed properly. rcParams are used during plotting. Sometimes the same theme can be achieved by setting rcParams before plotting or a apply after plotting. The choice of how to implement it is is a matter of convenience in that case. There are certain things can only be themed after plotting. There may not be an rcParam to control the theme or the act of plotting may cause an entity to come into existence before it can be themed. """


        try:
            rcParams = deepcopy(self._rcParams)
        except NotImplementedError:
            # deepcopy raises an error for objects that are drived from or
            # composed of matplotlib.transform.TransformNode.
            # Not desirable, but probably requires upstream fix.
            # In particular, XKCD uses matplotlib.patheffects.withStrok
            rcParams = copy(self._rcParams)

        for th in self.themeables.values():
            rcParams.update(th.rcParams)
        return rcParams