Python画置信区间图

import matplotlib.pyplot as plt
import seaborn as sns
import pandas as pd
import matplotlib as mpl
sns.set(font_scale=1.5)
#修改默认设置
mpl.rcParams["font.family"] = 'Times New Roman'  #默认字体类型
mpl.rcParams["mathtext.fontset"] = 'cm' #数学文字字体
mpl.rcParams["font.size"] = 20   #字体大小
mpl.rcParams["axes.linewidth"] = 1   #轴线边框粗细（默认的太粗了）
font = {'family' : 'Times New Roman',
        'color'  : 'black',
        'weight' : 'normal',
        'size'   : 25,
        }

region='1'
data=pd.read_csv(r'XXXXXX.csv')
data=data[data['species']=='Pygoscelis adeliae']



fig, ax = plt.subplots(figsize=(10,4))

x=data['season starting']
y=data['lower CI']
y1=data['upper CI']
mean=data['mean']


plt.plot(x, y, 'b',marker='.',markersize=0.0, linewidth=0.5)
plt.plot(x, y1, 'b',marker='.',markersize=0.0, linewidth=0.5)
plt.fill_between(x,y,y1,color='blue',alpha=0.15)
plt.plot(x, mean, 'k',marker='o',markersize=8, linewidth=0.5)
plt.title('Region'+region,fontdict=font)
plt.savefig('Region'+region+'.jpg',dpi=300)