pycharm想使用matplotlib进行画图时，在import阶段就开始报错

代码如下：

import matplotlib.pyplot as plt
import xlrd

x1 = []
y1 = []

data = xlrd.open_workbook(r'【修订版】附件1-道路节点工作点坐标.xlsx')
dljd = data.sheets()[0]
gzd = data.sheets()[1]

X1 = dljd.col_values(1)
Y1 = dljd.col_values(2)

print(X1)  # 打印出来检验是否正确读取

for i in range(len(x1)):
    x1.append(X1[i])
    y1.append(Y1[i])

plt.plot(x1, y1, 'bo-', linewidth=1)
plt.title('道路节点分布图')
plt.legend()

plt.xlabel('x')
plt.ylabel('y')
plt.show()

运行结果如下：

Traceback (most recent call last):
  File "F:/数学建模文件/2021暑期集训课件/练习题/第四次小组赛题/A题：汽车组装车间流水线物料配送问题/画图.py", line 1, in <module>
    import matplotlib.pyplot as plt
  File "D:\Python\lib\site-packages\matplotlib\pyplot.py", line 2500, in <module>
    switch_backend(rcParams["backend"])
  File "D:\Python\lib\site-packages\matplotlib\pyplot.py", line 277, in switch_backend
    class backend_mod(matplotlib.backend_bases._Backend):
  File "D:\Python\lib\site-packages\matplotlib\pyplot.py", line 278, in backend_mod
    locals().update(vars(importlib.import_module(backend_name)))
  File "D:\Python\lib\importlib\__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "D:\PyCharm 2020.2.3\plugins\python\helpers\pycharm_matplotlib_backend\backend_interagg.py", line 8, in <module>
    from matplotlib.backends.backend_agg import FigureCanvasAgg
  File "D:\Python\lib\site-packages\matplotlib\backends\backend_agg.py", line 44, in <module>
    from matplotlib.backends._backend_agg import RendererAgg as _RendererAgg
ModuleNotFoundError: No module named 'matplotlib.backends._backend_agg'

from matplotlib import pyplt as plt