python matplotlib以日期为x轴作图

from datetime import datetime, date, timedelta
import matplotlib.pyplot as plt
import tushare as ts

plt.rcParams['font.sans-serif'] = ['SimHei']  #显示中文
plt.rcParams['axes.unicode_minus']=False #用来正常显示负号

def get_riqi():
    count = 30
    i = 0
    today = date.today() #今天日期
    riqi_list=[]
    riqi_list.append(str(today))
    while(i<=count):
        i+=1
        riqi_list.append(str((today + timedelta(days=-i))))
    return riqi_list

def count(Data):
    data_list = []
    sum_list = []
    for data in Data:
        sum = 0
        list = []
        for jiage in data:
            sum+=jiage
            list.append(jiage)
        sum_list.append(round(sum,2))
        data_list.append(list)
    return sum_list,data_list

def get_juedui(Data):
    sum = 0
    data = []
    for i in Data[::-1]:
        sum += i
        data.append(sum)
    return data
technology = {
    '海康威视':'',
    '中兴通讯':'',
    '科大讯飞':'',
    '立讯精密':'',
    '蓝思科技':'',
    '歌尔股份':''
}
store = [technology]
technology = []
def get_data(store,riqi_list):
    count = 0
    for Stock_pool in store:
        count +=1
        for  stock in Stock_pool.values():
            data = ts.get_hist_data(stock,start=riqi_list[-1])
            if (count == 1):
                technology.append(data.loc[:, 'p_change'])
riqi_list = get_riqi()
get_data(store,riqi_list)
riqi_list = technology[0].index
rili = []
for riqi in riqi_list:
    rili.append(riqi[5:])
sum2,data2 = count(technology)
riqi_list = [datetime.strptime(d, '%m-%d').date() for d in rili]
count = 0
for i in data2:
    count+=1
    data = get_juedui(i)
    if(count==1):
     plt.plot(rili[::-1], data,label = '海康威视' )
    if(count==2):
     plt.plot(rili[::-1], data,label = '中兴通讯' )
    if(count==3):
     plt.plot(rili[::-1], data,label = '科大讯飞' )
    if(count==4):
     plt.plot(rili[::-1], data,label = '立讯精密' )
    if (count == 5):
     plt.plot(rili[::-1], data, label='蓝思科技')
    if (count == 6):
     plt.plot(rili[::-1], data, label='歌尔股份')
plt.legend()
plt.show()