code: def toxml(self):
          
  
          xmlstr = '<ConditionalDerivedVariable name="{0}"'.format(self.name) +\
            (' dimension="{0}"'.format(self.dimension) if self.dimension else '') +\
            (' exposure="{0}"'.format(self.exposure) if self.exposure else '') 
            
          chxmlstr = ''
  
          for case in self.cases:
              chxmlstr += case.toxml()
  
          if chxmlstr:
              xmlstr += '>' + chxmlstr + '</ConditionalDerivedVariable>'
          else:
              xmlstr += '/>'
              
          return xmlstr
docs: Exports this object into a LEMS XML object