def epw_file(self, value):
        """The path of the epw file that is to be converted to a wea file."""
        if value:
            self._epw_file = value
            if not self.output_wea_file._value:
                self.output_wea_file = os.path.splitext(value)[0] + '.wea'
        else:
            self._epw_file = None