text: """Record validation logic."""
  
  import logging
  # If Biopython is not available, all checks will return False
  try:
      from Bio import SeqIO
      from Bio.SeqFeature import BeforePosition, AfterPosition
      HAVE_BIOPYTHON = True
  except ImportError:  # pragma: no cover
      HAVE_BIOPYTHON = False
  
  
  VALIDATION_LEVELS = {'none', 'loads', 'all', 'correct'}
  
  
  def run_extended_validation(handle, file_format, validation_level):
      """Check if the dowloaded sequence file can load."""
      if not HAVE_BIOPYTHON:
          return False
      # we wrote to the handle, so rewind it
      handle.seek(0)
      try:
          processed_seq = False
          records = []
          for rec in SeqIO.parse(handle, file_format):
              processed_seq = True
              if validation_level == 'loads':
                  continue
              if validation_level == 'correct':
                  ## Correct possible errors from downloaded a restricted-range genbank file
                  ## Will write over the downloaded file
                  newfeats = []
                  for f in rec.features:
                      try:
                          if not isinstance(f.location.start, BeforePosition) and not isinstance(f.location.end, AfterPosition):
                              newfeats.append(f)
                      except AttributeError:
                          newfeats.append(f)
                  rec.features = newfeats
                  records.append(rec)
          if not processed_seq:
              logging.error('no seq')
  
          if validation_level == 'correct':
              ## rewrite StringIO data
              handle.truncate(0)
              handle.seek(0)
              SeqIO.write(records, handle, 'genbank')
          return processed_seq
      except (ValueError, AssertionError) as err:
          logging.error(err)
          return False
      except Exception as err:
          logging.error("Unhandled exception %s while parsing sequence file." % err)
          return False
  