安装之后输入 grank 出错

[MjSeven]

输入 grank login 之后报错
Traceback (most recent call last):
File "/home/mj/grank_work/bin/grank", line 7, in
from grank.core import main
File "/home/mj/grank_work/lib/python3.6/site-packages/grank/core.py", line 12, in
from .libs import helpers
File "/home/mj/grank_work/lib/python3.6/site-packages/grank/libs/helpers.py", line 12, in
import matplotlib.pyplot as plt
File "/home/mj/grank_work/lib/python3.6/site-packages/matplotlib/pyplot.py", line 2374, in
switch_backend(rcParams["backend"])
File "/home/mj/grank_work/lib/python3.6/site-packages/matplotlib/pyplot.py", line 207, in switch_backend
backend_mod = importlib.import_module(backend_name)
File "/home/mj/grank_work/lib/python3.6/importlib/init.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "/home/mj/grank_work/lib/python3.6/site-packages/matplotlib/backends/backend_tkagg.py", line 1, in
from . import _backend_tk
File "/home/mj/grank_work/lib/python3.6/site-packages/matplotlib/backends/_backend_tk.py", line 5, in
import tkinter as Tk
ModuleNotFoundError: No module named 'tkinter'

复现

1. pip install grank
2. grank login
   报错
   

之后再安装 tkinter 报错找不到，是我的操作有误？

系统

• OS: [Ubuntu 18]