在python 3.7.6 环境中，已经安装完依赖安装ipython，在安装jupyter时报错如下，请大佬们帮们解答，感谢感谢！
$ pip install jupyter
$ jupyter notebook help
[python@centos-mini-7 web]$ jupyter notebook help
Traceback (most recent call last):
File "/home/python/.pyenv/versions/mag376/bin/jupyter-notebook", line 5, in <module>
from notebook.notebookapp import main
File "/home/python/.pyenv/versions/3.7.6/envs/mag376/lib/python3.7/site-packages/notebook/notebookapp.py", line 49, in <module>
from zmq.eventloop import ioloop
File "/home/python/.pyenv/versions/3.7.6/envs/mag376/lib/python3.7/site-packages/zmq/__init__.py", line 57, in <module>
_load_libzmq()
File "/home/python/.pyenv/versions/3.7.6/envs/mag376/lib/python3.7/site-packages/zmq/__init__.py", line 19, in _load_libzmq
import ctypes
File "/home/python/.pyenv/versions/3.7.6/lib/python3.7/ctypes/__init__.py", line 7, in <module>
from _ctypes import Union, Structure, Array
ModuleNotFoundError: No module named '_ctypes'
