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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 getBigIndexFromIndices(self, indices):
 """ Get the big index from a given set of indices @param indices @return big index @note no checks are performed to ensure that the returned indices are valid """

        return reduce(operator.add, [self.dimProd[i]*indices[i]
                                     for i in range(self.ndims)], 0)