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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 make_grid_slot(self, n, m):
 """Create a n x m video grid, show it and add it to the list of video containers """

        def slot_func():
            cont = container.VideoContainerNxM(gpu_handler=self.gpu_handler, 
                                                    filterchain_group=self.filterchain_group, 
                                                    n_dim=n, 
                                                    m_dim=m)
            cont.signals.closing.connect(self.rem_container_slot)
            self.containers.append(cont)
        setattr(self, "grid_%ix%i_slot" % (n, m), slot_func)