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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 add_error(self, error):
 """Record an error from expect APIs. This method generates a position stamp for the expect. The stamp is composed of a timestamp and the number of errors recorded so far. Args: error: Exception or signals.ExceptionRecord, the error to add. """

        self._count += 1
        self._record.add_error('expect@%s+%s' % (time.time(), self._count),
                               error)