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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 _base_type(self):
 """Return str like 'enum.numeric' representing dimension type. This string is a 'type.subclass' concatenation of the str keys used to identify the dimension type in the cube response JSON. The '.subclass' suffix only appears where a subtype is present. """

        type_class = self._dimension_dict["type"]["class"]
        if type_class == "categorical":
            return "categorical"
        if type_class == "enum":
            subclass = self._dimension_dict["type"]["subtype"]["class"]
            return "enum.%s" % subclass
        raise NotImplementedError("unexpected dimension type class '%s'" % type_class)