<｜begin▁of▁sentence｜>### Instruction:
Given an Erdős-Rényi graph with 10 vertices and 5 edges, how can you determine the number of vertices in the graph using igraph?
### Response:
import igraph as ig

# Create a graph with 10 vertices and 5 edges
g = ig.Graph.Erdos_Renyi(n=10, m=5)

# Use the vcount method to count the number of vertices
vertex_count = g.vcount()

print(f'The graph has {vertex_count} vertices.')
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