Wrong change to set initialisation

Made this mistake before, it copies the same set

PopPUNK/network.py

@@ -1425,7 +1425,7 @@ def printClusters(G, rlist, outPrefix=None, oldClusterFile=None,
     if use_gpu:
         component_assignments = cugraph.components.connectivity.connected_components(G)
         component_frequencies = component_assignments['labels'].value_counts(sort = True, ascending = False)
-        newClusters = [set() for rank in range(component_frequencies.size)]
+        newClusters = [set() for _ in range(component_frequencies.size)]
         for isolate_index, isolate_name in enumerate(rlist): # assume sorted at the moment
             component = component_assignments['labels'].iloc[isolate_index].item()
             component_rank_bool = component_frequencies.index == component