Coconut is a compile-to-python(2/3) language, not just a library, so if you use it you have to be OK with using a transpiler in your project.

Here's one way you might write one of the examples in Coconut:

  ([1, 2, 3, 4]
      |> map$(-> _ * 2)
      |> filter$(-> _ > 4)
      |> reduce$((x, y) -> x + y)
  )

You may freely mix Coconut and Python in a project, even in the same file, but any Coconut code still needs to be run through the compiler.