<｜begin▁of▁sentence｜>### Instruction:
Given a graph with edge set [(0, 1), (1, 2), (2, 3), (3, 0), (0, 1), (1, 1)], how would you simplify the graph to remove self-loops and multiple edges using the igraph's 'simplify' function? The code should simplify the given graph and display the edges before and after simplification.
### Response:
from igraph import Graph

# Create a graph with multiple edges and self-loops
g = Graph(edges=[(0, 1), (1, 2), (2, 3), (3, 0), (0, 1), (1, 1)])

# Print the edges before simplification
print('Before simplification:', g)

# Simplify the graph by removing self-loops and multiple edges
g.simplify()

# Print the edges after simplification
print('After simplification:', g)
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