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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 _raw_weights(self):
 """Create a numpy array containing the raw sensor weights. """

        if self._debug:
            return np.array([[],[],[],[]])

        if not self._running:
            raise ValueError('Weight sensor is not running!')
        if len(self._weight_buffers) == 0:
            time.sleep(0.3)
            if len(self._weight_buffers) == 0:
                raise ValueError('Weight sensor is not retrieving data!')
        weights = np.array(self._weight_buffers)
        return weights