People in Shanghai are completely unable to produce their own food, with many not stocking even a bag of rice.
Meanwhile, there's plenty of rural areas that can produce family-sized amounts of eggs, milk, fruits, and veggies to survive on indefinitely should the government decide to blockade you.
During the holodomor hunger the government forbid getting food food even if your produced it yourself.
If you went into the fields after harvesting and tried getting anything that felt on the ground because you and your family were starving you were put to death.
Producing the food yourself makes no difference if the government takes it from you
People in Shanghai are completely unable to produce their own food, with many not stocking even a bag of rice.
Meanwhile, there's plenty of rural areas that can produce family-sized amounts of eggs, milk, fruits, and veggies to survive on indefinitely should the government decide to blockade you.