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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 _proc_group(self, style, adopt=True):
 """Return whether group is "default" or "override". In the case of "override", the self.fields pre-format and post-format processors will be set under the "override" key. Parameters style : dict A style that follows the schema defined in pyout.elements. adopt : bool, optional Merge `self.style` and `style`, giving priority to the latter's keys when there are conflicts. If False, treat `style` as a standalone style. """

        fields = self.fields
        if style is not None:
            if adopt:
                style = elements.adopt(self.style, style)
            elements.validate(style)

            for column in self.columns:
                fields[column].add(
                    "pre", "override",
                    *(self.procgen.pre_from_style(style[column])))
                fields[column].add(
                    "post", "override",
                    *(self.procgen.post_from_style(style[column])))
            return "override"
        else:
            return "default"