def METHOD_NAME(self):
    cp = subprocess.run(
        ['docker', 'compose', 'ps', '--format', 'json'],
        stdout=subprocess.PIPE, stderr=subprocess.PIPE,
        cwd=self.cwd,
    )
    if cp.returncode != 0:
        raise Exception(cp.stderr.decode('utf-8'))
    b_output = cp.stdout
    if len(b_output) > 0:
        self.containers = json.loads(b_output)