code: def migrateFileFields(portal):
      
      portal_types = [
          "Attachment",
          "ARImport",
          "Instrument",
          "InstrumentCertification",
          "Method",
          "Multifile",
          "Report",
          "ARReport",
          "SamplePoint"]
  
      for portal_type in portal_types:
          # Do the migration
          migrate_to_blob(
              portal,
              portal_type=portal_type,
              remove_old_value=True)
docs: This function walks over all attachment types and migrates their FileField
      fields.