code: def load_xml(self, xmlfile):
          
  
          self.logger.info('Loading XML')
  
          for c in self.components:
              c.load_xml(xmlfile)
  
          for name in self.like.sourceNames():
              self.update_source(name)
  
          self._fitcache = None
  
          self.logger.info('Finished Loading XML')
docs: Load model definition from XML.
  
          Parameters
          ----------
          xmlfile : str
              Name of the input XML file.