Move an interface to init_ne

Hello,

How to I move an interface back to the original namespace ?
I created three namespaces:

ip netns add namespace1
ip netns add namespace2
ip netns add namespace3

And move eth0 to namespace1:
ip link set  eth0 netns namespace1

How do I return it back to the original, default network namespace ? (init_net)

	
Regards,
DS