you can read this tutorial for how to use functions of statistical distributions in python. http://docs.scipy.org/doc/scipy/reference/tutorial/stats.html
from scipy.stats import norm
import matplotlib.pyplot as plt
import numpy as np
#initialize a normal distribution with frozen in mean=-1, std. dev.= 1
rv = norm(loc = -1., scale = 1.0)
rv1 = norm(loc = 0., scale = 2.0)
rv2 = norm(loc = 2., scale = 3.0)
x = np.arange(-10, 10, .1)
#plot the pdfs of these normal distributions
plt.plot(x, rv.pdf(x), x, rv1.pdf(x), x, rv2.pdf(x))