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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 maximum(self):
 """Maximum value of the object."""

        value = self._schema.get("maximum", None)
        if value is None:
            return
        if not isinstance(value, NUMERIC_TYPES):
            raise SchemaError(
                "maximum value {0!r} is not a numeric type".format(
                    value))
        return value