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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 dbclass(self, value):
 """Set the connection's dbclass property. Args: value: New dbclass value. String. Returns: Nothing. """


        if not is_valid_dbclass(value):
            raise AttributeError("'{}' is not a valid database type".format(value))

        self._class = value
        self._connectionXML.set('class', value)