import networkx as nx
import matplotlib.pyplot as plt

g = nx.Graph() 	# Creates a graph

g.add_edge(1, 2)  # Adds edge from node 1 to node 2
g.add_edge(1, 3)
g.add_node(4)	  # Adds node 4
print("Edges:", g.edges())
print("Nodes:", g.nodes())
print("Neighbors of node 1:", list(g.neighbors(1)))

assert len(g.nodes()) == 4
assert len(g.edges()) == 2

nx.draw_networkx(g)  # Draw the graph
plt.show()		     # Show the graph