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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 internal_tally(self):
 """Store the trace of stochastics for the computation of the covariance. This trace is completely independent from the backend used by the sampler to store the samples."""

        chain = []
        for stochastic in self.stochastics:
            chain.append(np.ravel(stochastic.value))
        self._trace.append(np.concatenate(chain))