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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add_block_widget(self, top=False):
 """ Return a select widget for blocks which can be added to this column. """

        widget = AddBlockSelect(attrs={
            'class': 'glitter-add-block-select',
        }, choices=self.add_block_options(top=top))

        return widget.render(name='', value=None)