CVXPY is a powerful Python modeling framework for convex optimization, similar to the MATLAB® counterpart CVX. ECOS is one of the default solvers in CVXPY, so there is nothing special you have to do in order to use ECOS with CVXPY, besides specifying it as a solver. Here is a small example from the CVXPY tutorial:
from cvxpy import *
# Solving a problem with different solvers.
x = Variable(2)
obj = Minimize(norm(x, 2) + norm(x, 1))
constraints = [x >= 2]
prob = Problem(obj, constraints)
# Solve with ECOS.
print "optimal value with ECOS:", prob.value