Random Number Error in Python

I get a random number generating error such as,

Traceback (most recent call last): File "C:\Users\SONY\Desktop\deneme.py", line 34, in update(x) File "C:\Users\SONY\Desktop\deneme.py", line 12, in update x[j] = x[j] + uniform(-1.4,1.4) NameError: global name 'uniform' is not defined

My code is as follows

N = 20

N_cor = 25
N_cf = 25
a = 0.5
eps = 1.4

def update(x):
    for j in range(0,N):
        old_x = x[j]
        old_Sj = S(j,x)
        x[j] = x[j] + uniform(-eps,eps)
        dS = S(j,x) - old_Sj
        if dS>0 and exp(-dS)<uniform(0,1):
            x[j] = old_x

def S(j,x):
    jp = (j+1)%N
    jm = (j-1)%N
    return a*x[j]**2/2 + x[j]*(x[j]-x[jp]-x[jm])/a

def compute_G(x,n):
    g = 0
    for j in range(0,N):
        g = g + x[j]*x[(j+n)%N]
        return g/N


x=[]
for j in range(0,N):
    x.append(0.0)
    print"x(%d)=%f"%(j,x[j])
for j in range(0,5*N_cor):
    update(x)
for alpha in range(0,N_cf):
    for j in range(0,N_cor):
        update(x)
    for n in range(0,N):
        G[alpha][n] = compute_G(x,n)
for n in range(0,N):
    avg_G = 0
    for alpha in range(0,N_cf):
        avg_G = avg_G + G[alpha][n]
        avg_G = avg_G / N_cf
        print "G(%d) = %f"%(n,avg_G)

Can you help me about how can i generate a uniform random number in range (-eps,eps) ?