Polar plot without grid in matplotlib

Is there a way to turn of the grid for polar plots in matplotlib? I tried matplotlib.pyplot.rgrids([], []), but it doesn't work.

From your axes instance, call grid(False).

import matplotlib.pyplot as plt
import numpy as np

fig = plt.figure()
ax = fig.add_subplot(111, polar=True)
ax.grid(False)

r = np.arange(0,1,0.001)
theta = 2*2*np.pi*r

ax.plot(theta,r)
plt.show()