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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 _update_transforms(X, S, R):
 """Updates the mappings `W_i` for each subject. Parameters X : list of 2D arrays, element i has shape=[voxels_i, timepoints] Each element in the list contains the fMRI data for alignment of one subject.ß S : list of array, element i has shape=[voxels_i, timepoints] The individual component :math:`S_i` for each subject. R : array, shape=[features, timepoints] The shared response. Returns ------- W : list of array, element i has shape=[voxels_i, features] The orthogonal transforms (mappings) :math:`W_i` for each subject. """

        subjs = len(X)
        W = []
        for i in range(subjs):
            W.append(RSRM._update_transform_subject(X[i], S[i], R))
        return W