Even if Julia wraps a library like Tensorflow, its API is looking really nice compared to Python [1]:
using TensorFlow
sess = TensorFlow.Session()
x = TensorFlow.constant(Float64[1,2])
y = TensorFlow.Variable(Float64[3,4])
z = TensorFlow.placeholder(Float64)
w = exp(x + z + -y)
run(sess, TensorFlow.global_variables_initializer())
res = run(sess, w, Dict(z=>Float64[1,2]))
Base.Test.@test res[1] ≈ exp(-1)
[1] https://github.com/malmaud/TensorFlow.jl