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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 nnz_obs(self):
 """ get the number of non-zero weighted observations Returns ------- nnz_obs : int the number of non-zeros weighted observations """

        nnz = 0
        for w in self.observation_data.weight:
            if w > 0.0:
                nnz += 1
        return nnz