python可视化---饼图

import matplotlib.pyplot as plt
import matplotlib as mpl

mpl.rcParams["font.sans-serif"] = ["SimHei"]
mpl.rcParams["axes.unicode_minus"] = False

labels = "A难度水平", "B难度水平", "C难度水平", "D难度水平"

students = [0.35, 0.15, 0.20, 0.30]

colors = ["#377eb8", "#4daf4a", "#984ea3", "#ff7f00"]
          
explode = (0.1, 0.1, 0.1, 0.1)

plt.pie(students, explode=explode, labels=labels, autopct="%3.1f%%",
        startangle=45, shadow=True, colors=colors)

plt.title("选择不同难度测试试卷的学生百分比")

plt.show()