code: def updatepLvlGrid(self):
          '''
          Update the grid of permanent income levels.  Currently only works for
          infinite horizon models (cycles=0) and lifecycle models (cycles=1).  Not
          clear what to do about cycles>1.  Identical to version in persistent
          shocks model, but pLvl=0 is manually added to the grid (because there is
          no closed form lower-bounding cFunc for pLvl=0).
  
          Parameters
          ----------
          None
  
          Returns
          -------
          None
          '''
          # Run basic version of this method
          PersistentShockConsumerType.updatepLvlGrid(self)
          for j in range(len(self.pLvlGrid)): # Then add 0 to the bottom of each pLvlGrid
              this_grid = self.pLvlGrid[j]
              self.pLvlGrid[j] = np.insert(this_grid,0,0.0001f updatepLvlGrid(self):
          '''
          Update the grid of permanent income levels.  Currently only works for
          infinite horizon models (cycles=0) and lifecycle models (cycles=1).  Not
          clear what to do about cycles>1.  Identical to version in persistent
          shocks model, but pLvl=0 is manually added to the grid (because there is
          no closed form lower-bounding cFunc for pLvl=0).
  
          Parameters
          ----------
          None
  
          Returns
          -------
          None
          '''
          # Run basic version of this method
          PersistentShockConsumerType.updatepLvlGrid(self)
          for j in range(len(self.pLvlGrid)): # Then add 0 to the bottom of each pLvlGrid
              this_grid = self.pLvlGrid[j]
              self.pLvlGrid[j] = np.insert(this_grid,0,0.0001)
docs: Update the grid of permanent income levels.  Currently only works for
          infinite horizon models (cycles=0) and lifecycle models (cycles=1).  Not
          clear what to do about cycles>1.  Identical to version in persistent
          shocks model, but pLvl=0 is manually added to the grid (because there is
          no closed form lower-bounding cFunc for pLvl=0).
  
          Parameters
          ----------
          None
  
          Returns
          -------
          None