So I have a plot but I do not get how to add data labels to my figures. I get the desired plots but I would like to see the y-value for each point. Here is the code:
list_of_centers=os.listdir("./")
for i in range(len(list_of_centers)):
    xls = pd.ExcelFile("./"+list_of_centers[i])
    for j in range(len(xls.sheet_names)):
        df=pd.read_excel("./"+list_of_centers[i])
        df=df.drop(columns=['Y', 'C','O','Y_C','Y_O'])
        df=df.set_index('Date')
        lines = df.plot.line(title=list_of_centers[i][:-5]+"_"+xls.sheet_names[j])
    #add labels
        plt.savefig("./"+list_of_centers[i] 
        [:-5]+"_"+xls.sheet_names[j]+".png")