title: SQLAlchemy: assign TypeDecorator for the mapping generated via automap
body: <p>SQLAlchemy has two abilities:</p>
  
  <ol>
  <li><a href="http://docs.sqlalchemy.org/en/latest/orm/extensions/automap.html" rel="nofollow">reflect database to create mapping in runtime</a></li>
  <li><a href="http://docs.sqlalchemy.org/en/latest/core/custom_types.html#overriding-type-compilation" rel="nofollow">and customize columns type conversion</a></li>
  </ol>
  
  <p>I would like to combine these abilities: reflect database and then assign TypeDecorator for specific columns of specific tables.</p>
  
  <p>I have spent a lot of time trying to do this but had no result. The SQLAlchemy manual does not describe how to assign TypeDecorator for the  mapping generated via automap.</p>
  
  <p>I would like to know whether it's possible and if yes, how to achive my goal.</p>
  
  <p>Thank you!</p>