def __call__( self, *args, **kwargs ):
        if len( args ) > 1:
            raise ArgumentError( self.tag )

        # if class_ was defined in parent it should be added to every element
        if self.parent is not None and self.parent.class_ is not None:
            if 'class_' not in kwargs:
                kwargs['class_'] = self.parent.class_
            
        if self.parent is None and len( args ) == 1:
            x = [ self.render( self.tag, False, myarg, mydict ) for myarg, mydict in _argsdicts( args, kwargs ) ]
            return '\n'.join( x )
        elif self.parent is None and len( args ) == 0:
            x = [ self.render( self.tag, True, myarg, mydict ) for myarg, mydict in _argsdicts( args, kwargs ) ]
            return '\n'.join( x )
            
        if self.parent.twotags in self.tag:
            for myarg, mydict in _argsdicts( args, kwargs ):
                self.render( self.tag, False, myarg, mydict )
        elif self.tag in self.parent.onetags:
            if len( args ) == 0:
                for myarg, mydict in _argsdicts( args, kwargs ):
                    self.render( self.tag, True, myarg, mydict )    # here myarg is always None, because len( args ) = 0
            else:
                raise ClosingError( self.tag )
        elif self.parent.mode == 'strict_html' and self.tag in self.parent.deptags:
            raise DeprecationError( self.tag )
        else:
            raise InvalidElementError( self.tag, self.parent.mode )
dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/tablib-0.10.0/tablib/packages/markup3.py/element.__call__/swapped operands of `in`