b = Counter()
for word_pair in a:
    b[word_pair] += 1

n = len(states)
c = np.zeros((n, n),dtype = float)
states = list(states)
print(states)
for i in range(n):
    for j in range(n):
        c[i, j] = b[(states[i], states[j])]
print(c)