<｜begin▁of▁sentence｜>### Instruction:
As a clinical psychologist, imagine you are working with a team of researchers collecting data from a social network of patients with mental health disorders. The network represents relationships and interactions between patients, and each patient is assigned a 'group' attribute based on their diagnosis or treatment plan. You want to analyze the network to identify clusters of patients who share similar group memberships. Using the igraph library's `VertexClustering.FromAttribute` function, how can you create a vertex clustering based on these group attributes and examine the details of the first identified cluster within the social network?
### Response:
import igraph as ig

# Load the graph
g = ig.Graph.Read('network.gml')

# Create a vertex clustering based on a vertex attribute called 'group'
vertex_clustering = ig.VertexClustering.FromAttribute(g, attribute='group')

# Print the number of clusters in the clustering
print(len(vertex_clustering))

# Print the members of the first (index 0) cluster
print(vertex_clustering[0])
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