<｜begin▁of▁sentence｜>### Instruction:
Given an Erdős-Rényi graph with 10 vertices and 20 edges, can you use the `layout()` function to compute the Kamada-Kawai layout and then use the special `__len__` method to find out how many vertex positions are defined in this layout? Your task is to print the number of vertex positions.
### Response:
from igraph import Graph

# Create a simple graph
g = Graph.Erdos_Renyi(n=10, m=20)
layout = g.layout('kk')

# Get the number of positions in the layout, which corresponds to the number of vertices
print(len(layout))
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