没有 tkinter，抛出下面问题：
Traceback (most recent call last):
File "./wx.analyse_signature.py", line 21, in <module>
import matplotlib.pyplot as plt
File "/usr/lib/python3.7/site-packages/matplotlib/pyplot.py", line 2374, in <module>
switch_backend(rcParams["backend"])
File "/usr/lib/python3.7/site-packages/matplotlib/pyplot.py", line 207, in switch_backend
backend_mod = importlib.import_module(backend_name)
File "/usr/lib/python3.7/importlib/__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "/usr/lib/python3.7/site-packages/matplotlib/backends/backend_tkagg.py", line 1, in <module>
from . import _backend_tk
File "/usr/lib/python3.7/site-packages/matplotlib/backends/_backend_tk.py", line 5, in <module>
import tkinter as Tk
File "/usr/lib/python3.7/tkinter/__init__.py", line 36, in <module>
import _tkinter # If this fails your Python may not be configured for Tk
ImportError: libtk8.6.so: cannot open shared object file: No such file or directory
安装方法：
sudo pacman -S tk
