docs: def initialize_weights_nn(data, means, lognorm=True):
      """
      Initializes the weights with a nearest-neighbor approach using the means.
      """
      # TODO
      genes, cells = data.shape
      k = means.shape[1]
      if lognorm:
          data = log1p(cell_normalize(data))
      for i in range(cells):
          for j in range(k):
              pass