Fix Python – Generating a PNG with matplotlib when DISPLAY is undefined

I am trying to use networkx with Python. When I run this program it get this error. Is there anything missing?
#!/usr/bin/env python

import networkx as nx
import matplotlib
import matplotlib.pyplot
import matplotlib.pyplot as plt

G=nx.Graph()
G.add_node(1)
G.add_nodes_from([2,3,4,5,6,7,8,9,10])
#nx.draw_graphviz(G)
#nx_write_dot(G, ‘node.png’)
n….

Fix Python – Python Graph Library [closed]

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