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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 check_last_err(func, self, *args, **kwargs):
 """Check and raise deferred errors before running the function This method checks :python:`_last_err` before running the wrapped function. If present and not None, the exception will be raised with its original traceback. """


    if self._last_err is not None:
        try:
            if six.PY2:
                six.reraise(type(self._last_err), self._last_err,
                            self._last_tb)
            else:
                # NB(directxman12): not using six.reraise in Python 3 leads
                #                   to cleaner tracebacks, and raise x is valid
                #                   syntax in Python 3 (unlike raise x, y, z)
                raise self._last_err
        finally:
            if six.PY2:
                del self._last_tb  # in case of cycles, break glass

            self._last_err = None
    else:
        return func(self, *args, **kwargs)

    @deco.decorator
    def check_last_err(func, self, *args, **kwargs):
        if self._last_err is not None:
            try:
                raise self._last_err
            finally:
                self._last_err = None
        else:
            return func(self, *args, **kwargs)