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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 _on_process_error(self, error):
 """ Logs process error """

        if self is None:
            return
        if error not in PROCESS_ERROR_STRING:
            error = -1
        if not self._prevent_logs:
            _logger().warning(PROCESS_ERROR_STRING[error])