Histogram without bars

import numpy as np
import matplotlib.pyplot as plt

# Data in numpy array
data = np.array([12, 15, 13, 20, 19, 20, 11, 19, 11, 12, 19, 13,
                 12, 10, 6, 19, 3, 1, 1, 0, 4, 4, 6, 5, 3, 7,
                 12, 7, 9, 8, 12, 11, 11, 18, 19, 18, 19, 3, 6,
                 5, 6, 9, 11, 10, 14, 14, 16, 17, 17, 19, 0, 2,
                 0, 3, 1, 4, 6, 6, 8, 7, 7, 6, 7, 11, 11, 10,
                 11, 10, 13, 13, 15, 18, 20, 19, 1, 10, 8, 16,
                 19, 19, 17, 16, 11, 1, 10, 13, 15, 3, 8, 6, 9,
                 10, 15, 19, 2, 4, 5, 6, 9, 11, 10, 9, 10, 9,
                 15, 16, 18, 13])

bins, edges = np.histogram(data, 21, normed=1)
left, right = edges[:-1], edges[1:]
X = np.array([left, right]).T.flatten()
Y = np.array([bins, bins]).T.flatten()

plt.plot(X, Y)
plt.show()