Network: do not check existence at __init__

This causes a verbose error on normal behaviour that cannot be muted

lxc_net/network.py

@@ -4,8 +4,6 @@ from . import settings
 from . import util
 from .xml_template import XMLTemplate
 
-import libvirt
-
 
 class Network(util.LibvirtObject):
     class AlreadyExists(Exception):
@@ -18,19 +16,13 @@ class Network(util.LibvirtObject):
         if not name:
             name = str(self.id)
 
-        self.name = settings.PREFIX + "_" + name
+        self.name = settings.PREFIX + "_link_" + name
         self.bridge_id = settings.NETWORK_ID * 0xFF + self.id
         self.bridge_mac = util.MACAddress(self.id, None)
         self.ipv4 = util.Addrv4(self.id, None)
         self.ipv6 = util.Addrv6(self.id, None)
         self.lxc_network = None
 
-        try:
-            if self.conn.networkLookupByName(self.name):
-                raise self.AlreadyExists()
-        except libvirt.libvirtError:
-            pass
-
     def create(self):
         if self.lxc_network:
             raise self.AlreadyExists()