python: Use builtin len() function for network interfaces
python: Use builtin len() function for network interfaces

Use our own len() function for network interfaces as doing
len(container.get_config_item("lxc.network")) will fail when the
list is empty.

Signed-off-by: Stéphane Graber <089afc6d81f66f1168a9849e15660feae286e024@ubuntu.com>
Acked-by: Serge E. Hallyn <3df611b026e4639bee8aef7a4beb2e39fcebb313@ubuntu.com>

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