code: def str_cmd(cmd, cwd, env):
    
    process = subprocess.Popen(cmd, stdout=subprocess.PIPE,
                               stderr=subprocess.PIPE, cwd=cwd, env=env)
    stdout_builder, stderr_builder = proc.async_stdout_stderr_builder(process)
    process.wait()
    stdout, stderr = stdout_builder.result(), stderr_builder.result()
    return {'command': ' '.join(cmd), 'stderr': stderr, 'stdout': stdout}
docs: Runs the command and returns its stdout and stderr.