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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 dense_to_one_hot(labels_dense, num_classes):
 """Convert class labels from scalars to one-hot vectors."""

        num_labels = labels_dense.shape[0]
        index_offset = np.arange(num_labels) * num_classes
        labels_one_hot = np.zeros((num_labels, num_classes))
        labels_one_hot.flat[index_offset + labels_dense.ravel()] = 1
        return labels_one_hot