You can try this :
from rpy import *
And then you can use the object called r to do computations just like you would do in R.
Here is an example extracted from the doc:
>>> from rpy import *
>>>
>>> degrees = 4
>>> grid = r.seq(0, 10, length=100)
>>> values = [r.dchisq(x, degrees) for x in grid]
>>> r.par(ann=0)
>>> r.plot(grid, values, type=’lines’)