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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 dimension_type(self):
 """Return member of DIMENSION_TYPE appropriate to dimension_dict."""

        base_type = self._base_type
        if base_type == "categorical":
            return self._resolve_categorical()
        if base_type == "enum.variable":
            return self._resolve_array_type()
        if base_type == "enum.datetime":
            return DT.DATETIME
        if base_type == "enum.numeric":
            return DT.BINNED_NUMERIC
        if base_type == "enum.text":
            return DT.TEXT
        raise NotImplementedError("unrecognized dimension type %s" % base_type)