old_contents: from sqlalchemy.sql import functions
  
  from . import types
  
  __all__ = [
          'GenericFunction',
          'GeometryType',
          'AsText',
          'Buffer'
          ]
  
  
  class GenericFunction(functions.GenericFunction):
  
      def __init__(self, *args, **kwargs):
          expr = kwargs.pop('expr', None)
          if expr is not None:
              args = (expr,) + args
          functions.GenericFunction.__init__(self, *args, **kwargs)
  
  
  # Functions are classified as in the PostGIS doc.
  # <http://www.postgis.org/documentation/manual-svn/reference.html>
  
  
  #
  # Geometry Accessors
  #
  
  
  class GeometryType(GenericFunction):
      name = 'ST_GeometryType'
  
  
  #
  # Geometry Outputs
  #
  
  
  class AsText(GenericFunction):
      name = 'ST_AsText'
  
  
  #
  # Geometry Processing
  #
  
  
  class Buffer(GenericFunction):
      name = 'ST_Buffer'
      type = types.Geometry
  
new_contents: from sqlalchemy.sql import functions
  
  from . import types
  
  __all__ = [
          'GenericFunction',
          'GeometryType',
          'AsText',
          'Area',
          'Buffer'
          ]
  
  
  class GenericFunction(functions.GenericFunction):
  
      def __init__(self, *args, **kwargs):
          expr = kwargs.pop('expr', None)
          if expr is not None:
              args = (expr,) + args
          functions.GenericFunction.__init__(self, *args, **kwargs)
  
  
  # Functions are classified as in the PostGIS doc.
  # <http://www.postgis.org/documentation/manual-svn/reference.html>
  
  
  #
  # Geometry Accessors
  #
  
  
  class GeometryType(GenericFunction):
      name = 'ST_GeometryType'
  
  
  #
  # Geometry Outputs
  #
  
  
  class AsText(GenericFunction):
      name = 'ST_AsText'
  
  #
  # Spatial Relationships and Measurements
  #
  
  
  class Area(GenericFunction):
      name = 'ST_Area'
  
  
  #
  # Geometry Processing
  #
  
  
  class Buffer(GenericFunction):
      name = 'ST_Buffer'
      type = types.Geometry
  
subject: add ST_Area function