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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_object(self, obj):
        '''add an object to a later'''
        state = self.state
        if not obj.layer in state.layers:
            # its a new layer
            state.layers[obj.layer] = {}
        state.layers[obj.layer][obj.key] = obj
        state.need_redraw = True