@property<EOL><INDENT>def CO2(self):<DEDENT>
return self._CO2<EOL>
Property of AplusBT_CO2 parameter CO2.

        :getter:    Returns the CO2 concentration which is stored in attribute
                    ``self._CO2``
        :setter:    * sets the CO2 concentration which is addressed as ``self._CO2``
                      to the new value
                    * updates the parameter dictionary ``self.param['CO2']``
        :type:      float