A simple wrapper around subprocess.Popen to reduce the painfulness of running
multiple processes concurrently.
task = Subtask(['python', 'hello.py'])
task.wait()
assert task.read_stdout().strip() == "Hello, world!"Subtask makes it easy to keep track of many concurrent subprocesses. It makes it much easier to capture outputs and give inputs to these processes.
Subtask is designed for simplicity. It should not be used if you want high performance, or to chain outputs for many files together.