code: def reconstruct_spectra(data):
      """Compute the reconstructed spectra.
  
      Parameters
      ----------
      data: NpzFile
          numpy data object returned by fetch_sdss_corrected_spectra.
  
      Returns
      -------
      spec_recons: ndarray
          Reconstructed spectra, using principal components to interpolate
          across the masked region.
      """
      spectra = data["spectra"]
      coeffs = data["coeffs"]
      evecs = data["evecs"]
      mask = data["mask"]
      mu = data["mu"]
      norms = data["norms"]
  
      spec_recons = spectra.copy()
  
      nev = coeffs.shape[1]
  
      spec_fill = mu + np.dot(coeffs, evecs[:nev])
      spec_fill *= norms[:, np.newaxis]
  
      spec_recons[mask] = spec_fill[mask]
  
      return spec_recons
  
imports: import os
  import numpy
  from .None import get_data_home
  from .tools import download_with_progress_bar
label_desc: Use image node_id 1 for calling a global function with example usage: reconstruct_spectra(data) and returns: spec_recons