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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 _init_methods(self):
 """Convert all pure Python calculation functions of the model class to methods and assign them to the model instance. """

        for name_group in self._METHOD_GROUPS:
            functions = getattr(self, name_group, ())
            uniques = {}
            for func in functions:
                name_func = func.__name__
                method = types.MethodType(func, self)
                setattr(self, name_func, method)
                shortname = '_'.join(name_func.split('_')[:-1])
                if shortname in uniques:
                    uniques[shortname] = None
                else:
                    uniques[shortname] = method
            for (shortname, method) in uniques.items():
                if method is not None:
                    setattr(self, shortname, method)