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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_xml(self, xmlfile):
 """Load model definition from XML. Parameters xmlfile : str Name of the input XML file. """


        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')