Python code to plot a .wav file

plot_wav.py

# Load the required libraries:
#   * scipy
#   * numpy
#   * matplotlib
from scipy.io import wavfile
from matplotlib import pyplot as plt
import numpy as np

# Load the data and calculate the time of each sample
samplerate, data = wavfile.read('Clapping.wav')
times = np.arange(len(data))/float(samplerate)

# Make the plot
# You can tweak the figsize (width, height) in inches
plt.figure(figsize=(30, 4))
plt.fill_between(times, data[:,0], data[:,1], color='k') 
plt.xlim(times[0], times[-1])
plt.xlabel('time (s)')
plt.ylabel('amplitude')
# You can set the format by changing the extension
# like .pdf, .svg, .eps
plt.savefig('plot.png', dpi=100)
plt.show()

I'm getting:

OverflowError: Allocated too many blocks

how do i represent single channel with two different colors