代码：
# -*- coding: utf-8 -*-
import pandas as pd
from matplotlib import pyplot as plt
hot_dog = pd.read_csv(r"matplotlib_bar/csv/hot-dog-contest-winners.csv")
def plot():
# ********* Begin *********#
fig, ax = plt.subplots() #subplots返回画布和子图
ax.bar(hot_dog["Year"],hot_dog["Dogs eaten"]) #绘制柱形图，第一个参数为x轴变量，第二个参数为y轴变量
plt.show() #显示图像
# ********* End *********#
plt.savefig('matplotlib_bar/studentfile/studentanswer/level_1/US.png')
plt.close()
