<｜begin▁of▁sentence｜>### Instruction:
As a demographer, you have been provided with a network graph representing a community network, called community_network.gml. After performing community detection using edge betweenness, you are interested in identifying the size of the first detected cluster. To achieve this, you want to utilize the length attribute of the VertexClustering object in igraph. How would you use the length attribute to find out the size of the first detected cluster?
### Response:
from igraph import Graph
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