Exports this object into a LEMS XML object

def toxml(self):
        """
        Exports this object into a LEMS XML object
        """

        return '<Constant' +\
          (' name = "{0}"'.format(self.name) if self.name else '') +\
          (' symbol = "{0}"'.format(self.symbol) if self.symbol else '') +\
          (' value = "{0}"'.format(self.value) if self.value else '') +\
          (' dimension = "{0}"'.format(self.dimension) if self.dimension else '') +\
          (' description = "{0}"'.format(self.description) if self.description else '') +\
          '/>'