code: def read_iter(use_fpi):
      '''Return the path to the final .mag file either for the complex or the fpi
      inversion.
      '''
      filename_rhosuffix = 'exe/inv.lastmod_rho'
      filename = 'exe/inv.lastmod'
      # filename HAS to exist. Otherwise the inversion was not finished
      if(not os.path.isfile(filename)):
          print('Inversion was not finished! No last iteration found.')
  
      if(use_fpi is True):
          if(os.path.isfile(filename_rhosuffix)):
              filename = filename_rhosuffix
  
      linestring = open(filename, 'r').readline().strip()
      linestring = linestring.replace('\n', '')
      linestring = linestring.replace('../', '')
      return linestrinf read_iter(use_fpi):
      '''Return the path to the final .mag file either for the complex or the fpi
      inversion.
      '''
      filename_rhosuffix = 'exe/inv.lastmod_rho'
      filename = 'exe/inv.lastmod'
      # filename HAS to exist. Otherwise the inversion was not finished
      if(not os.path.isfile(filename)):
          print('Inversion was not finished! No last iteration found.')
  
      if(use_fpi is True):
          if(os.path.isfile(filename_rhosuffix)):
              filename = filename_rhosuffix
  
      linestring = open(filename, 'r').readline().strip()
      linestring = linestring.replace('\n', '')
      linestring = linestring.replace('../', '')
      return linestring
docs: Return the path to the final .mag file either for the complex or the fpi
      inversion.