code: def from_json(cls, json_moc):
          
          intervals = np.array([])
          for order, pix_l in json_moc.items():
              if len(pix_l) == 0:
                  continue
              pix = np.array(pix_l)
              p1 = pix
              p2 = pix + 1
              shift = 2 * (AbstractMOC.HPY_MAX_NORDER - int(order))
  
              itv = np.vstack((p1 << shift, p2 << shift)).T
              if intervals.size == 0:
                  intervals = itv
              else:
                  intervals = np.vstack((intervals, itv))
  
          return cls(IntervalSet(intervals))
docs: Creates a MOC from a dictionary of HEALPix cell arrays indexed by their depth.
  
          Parameters
          ----------
          json_moc : dict(str : [int]
              A dictionary of HEALPix cell arrays indexed by their depth.
  
          Returns
          -------
          moc : `~mocpy.moc.MOC` or `~mocpy.tmoc.TimeMOC`
              the MOC.