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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 srcmdl_xml(self, **kwargs):
 """ return the file name for source model xml files """

        kwargs_copy = self.base_dict.copy()
        kwargs_copy.update(**kwargs)
        localpath = NameFactory.srcmdl_xml_format.format(**kwargs_copy)
        if kwargs.get('fullpath', False):
            return self.fullpath(localpath=localpath)
        return localpath