text: # dialects/__init__.py
  # Copyright (C) 2005-2016 the SQLAlchemy authors and contributors
  # <see AUTHORS file>
  #
  # This module is part of SQLAlchemy and is released under
  # the MIT License: http://www.opensource.org/licenses/mit-license.php
  
  __all__ = (
      'firebird',
      'mssql',
      'mysql',
      'oracle',
      'postgresql',
      'sqlite',
      'sybase',
  )
  
  from .. import util
  
  
  def _auto_fn(name):
      """default dialect importer.
  
      plugs into the :class:`.PluginLoader`
      as a first-hit system.
  
      """
      if "." in name:
          dialect, driver = name.split(".")
      else:
          dialect = name
          driver = "base"
      try:
          module = __import__('sqlalchemy.dialects.%s' % (dialect, )).dialects
      except ImportError:
          return None
  
      module = getattr(module, dialect)
      if hasattr(module, driver):
          module = getattr(module, driver)
          return lambda: module.dialect
      else:
          return None
  
  registry = util.PluginLoader("sqlalchemy.dialects", auto_fn=_auto_fn)
  