I think you can use np.cumsum http://docs.scipy.org/doc/numpy/reference/generated/numpy.cumsum.html:
>>>y = np.arange(0,1,0.1)
>>>[ 0. 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9]
>>>y_cum = np.cumsum(y)
>>>[ 0. 0.1 0.3 0.6 1. 1.5 2.1 2.8 3.6 4.5]
Edit:
Using your example coordinates I get the following outputs:
x,y = bezier(np.arange(0,1,0.01))
plot(x,y)
plot(np.cumsum(x),np.cumsum(y))
Assuming this is what you are looking for!