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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 _resolve_categorical(self):
 """Return one of the categorical members of DIMENSION_TYPE. This method distinguishes between CAT, CA_CAT, MR_CAT, and LOGICAL dimension types, all of which have the base type 'categorical'. The return value is only meaningful if the dimension is known to be one of the categorical types (has base-type 'categorical'). """

        # ---an array categorical is either CA_CAT or MR_CAT---
        if self._is_array_cat:
            return DT.MR_CAT if self._has_selected_category else DT.CA_CAT

        # ---what's left is logical or plain-old categorical---
        return DT.LOGICAL if self._has_selected_category else DT.CAT