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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 add_theme(self, other, inplace=False):
 """Add themes together. Subclasses should not override this method. This will be called when adding two instances of class 'theme' together. A complete theme will annihilate any previous themes. Partial themes can be added together and can be added to a complete theme. """

        if other.complete:
            return other

        theme_copy = self if inplace else deepcopy(self)
        theme_copy.themeables.update(deepcopy(other.themeables))
        return theme_copy