A is not B

isnot.py

import networkx as nx
import matplotlib.pyplot as plt

isnot = [('Spain', 'Greece'),
        ('Portugal', 'Greece'),
        ('Greece', 'Ireland'),
        ('Spain', 'Ireland'),
        ('Spain', 'Portugal'),
        ('Ireland', 'Greece'),
        ('Portugal', 'Ireland'),
        ('Spain', 'Uganda'),
        ('Uganda', 'Spain')]

flat = list(set([country for c in isnot for country in c]))

G = nx.Graph()

for c in flat:
    G.add_node(c)
G.add_edges_from(isnot)

H = nx.DiGraph(G)

nx.draw(H)
plt.show()