docs: def import_tables(self, only_tables=None, exclude_tables=None):
          """Imports all data in database tables
  
          :param set[str] only_tables: names of tables to be imported
          :param set[str] exclude_tables: names of tables to be excluded
          """
          for table in self.tables:
              if only_tables is not None and table.name not in only_tables:
                  continue
  
              if exclude_tables is not None and table.name in exclude_tables:
                  continue
              self.import_table(table)