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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 err_write(self, msg, **kwargs):
 r"""Print `msg` as an error message. The message is buffered (won't display) until linefeed ("\n"). """

        if self._thread_invalid():
            # special case: if a non-main thread writes to stderr
            # i.e. due to an uncaught exception, pass it through
            # without raising an additional exception.
            self.async_call(self.err_write, msg, **kwargs)
            return
        return self.request('nvim_err_write', msg, **kwargs)