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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 _reset_errors(self, msg=None):
 """ Resets the logging throttle cache, so the next error is emitted regardless of the value in `self.server_error_interval` :param msg: if present, only this key is reset. Otherwise, the whole cache is cleaned. """

        if msg is not None and msg in self._errors:
            del self._errors[msg]
        else:
            self._errors = {}