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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 __generate_method(name):
 """ Wraps the DataFrame's original method by name to return the derived class instance. """

        try:
            func = getattr(DataFrame, name)
        except AttributeError as e:
            # PySpark version is too old
            def func(self, *args, **kwargs):
                raise e
            return func
        wraps = getattr(functools, "wraps", lambda _: lambda f: f)  # py3.4+

        @wraps(func)
        def _wrapper(self, *args, **kwargs):
            dataframe = func(self, *args, **kwargs)
            if self.__class__ != SourcedDataFrame \
                    and isinstance(self, SourcedDataFrame) \
                    and isinstance(dataframe, DataFrame):
                return self.__class__(dataframe._jdf, self._session, self._implicits)
            return dataframe

        return _wrapper