def __getattr__(self, item, default=None):
        """ Reference the new attribute and warn about deprecation. """
        if item == OLD_PIPES_KEY:
            _warn_pipes_deprecation()
            item = NEW_PIPES_KEY
        return super(_Metadata, self).__getattr__(item, default=None)
def __getattr__ ( self , item , default = None ) : if item == OLD_PIPES_KEY : _warn_pipes_deprecation ( ) item = NEW_PIPES_KEY return super ( _Metadata , self ) . __getattr__ ( item , default = None )
Reference the new attribute and warn about deprecation.