code: def _get_sqla_coltype_class_from_str(coltype: str,
                                       dialect: Dialect) -> Type[TypeEngine]:
      
      # noinspection PyUnresolvedReferences
      ischema_names = dialect.ischema_names
      try:
          return ischema_names[coltype.upper()]
      except KeyError:
          return ischema_names[coltype.lower()]
docs: Returns the SQLAlchemy class corresponding to a particular SQL column
      type in a given dialect.
  
      Performs an upper- and lower-case search.
      For example, the SQLite dialect uses upper case, and the
      MySQL dialect uses lower case.