code: def epoch_to_dttm(cls) -> str:
      return "from_unixtime({col})"
  
imports: import contextlib
  import re
  from datetime import datetime
  from decimal import Decimal
  from re import Pattern
  from typing import Any, Callable, Optional
  from urllib import parse
  from flask_babel import gettext
  from sqlalchemy import types
  from sqlalchemy.dialects.mysql import BIT, DECIMAL, DOUBLE, FLOAT, INTEGER, LONGTEXT, MEDIUMINT, MEDIUMTEXT, TINYINT, TINYTEXT
  from sqlalchemy.engine.url import URL
  from superset.constants import TimeGrain
  from superset.db_engine_specs.base import BaseEngineSpec, BasicParametersMixin
  from superset.errors import SupersetErrorType
  from superset.models.sql_lab import Query
  from superset.utils.core import GenericDataType
label_desc: Use image node_id 5 for calling the MySQLEngineSpec obj's underlying member method code with example usage: obj.epoch_to_dttm(cls) and returns: str