code: def add_low_rank_one(U, P):
      """Efficient addition of low-rank matrices (symmetric)."""
      return np.concatenate((U, P), axis=1)
  
imports: import collections
  from functools import partial
  import numpy
  from scipy.sparse.linalg import svds
  from sklearn.base import BaseEstimator, TransformerMixin
  from sktime.dists_kernels.base import BasePairwiseTransformerPanel
label_desc: Use image node_id 21 for calling a global function with example usage: add_low_rank_one(U, P) and returns: np