我在Windows 10上运行以下Python文件：

import subprocess

subprocess.call("dir")

但我得到了以下错误：

File "A:/python-tests/subprocess_test.py", line 10, in <module>
    subprocess.call(["dir"])

  File "A:\anaconda\lib\subprocess.py", line 267, in call
    with Popen(*popenargs, **kwargs) as p:

  File "A:\anaconda\lib\site-packages\spyder\utils\site\sitecustomize.py", line 210, in __init__
    super(SubprocessPopen, self).__init__(*args, **kwargs)

  File "A:\anaconda\lib\subprocess.py", line 709, in __init__
    restore_signals, start_new_session)

  File "A:\anaconda\lib\subprocess.py", line 997, in _execute_child
    startupinfo)

FileNotFoundError: [WinError 2] The system cannot find the file specified

请注意，我在这里只使用dir作为示例，实际上我想运行一个更复杂的命令，但在这种情况下也会得到相同的错误。
请注意，我没有使用shell=True，因此这个问题的答案不适用：Cannot find the file specified when using subprocess.call('dir', shell=True) in Python
这是subprocess.py的第997行：

hp, ht, pid, tid = _winapi.CreateProcess(executable, args,
                                         # no special security
                                         None, None,
                                         int(not close_fds),
                                         creationflags,
                                         env,
                                         os.fspath(cwd) if cwd is not None else None,
                                         startupinfo)

当我运行调试器检查传递给CreateProcess的参数时，我注意到executable是None，这正常吗？