code: def write_files(self):
          
          warnings = self.validate_data()
  
          print('-I- Writing all saved data to files')
          if self.measurements:
              self.write_measurements_file()
          for dtype in ['specimen', 'sample', 'site']:
              if self.data_lists[dtype][0]:
                  do_pmag = dtype in self.incl_pmag_data
                  self.write_magic_file(dtype, do_er=True, do_pmag=do_pmag)
                  if not do_pmag:
                      pmag_file = os.path.join(self.WD, 'pmag_' + dtype + 's.txt')
                      if os.path.isfile(pmag_file):
                          os.remove(pmag_file)
  
          if self.locations:
              self.write_magic_file('location', do_er=True, do_pmag=False)
  
          self.write_age_file()
  
          if self.results:
              self.write_result_file()
  
          if warnings:
              print('-W- ' + str(warnings))
              return False, warnings
  
          return True, None
docs: write all data out into er_* and pmag_* files as appropriate