Tkinter loops

[mattemio]

Hi guys!
I'm an absolute newbie in python.
I have this problem with tk inter:

class months():
    def __init__ (self,name,days_of_the_month,year):
        mesi.name = nome
        mesi.days = days_of_the_month
        mesi.year = year


january= months('January',31,2020)
february= months('February',29,2020)
.
.
.  
december= months('December',31,2020)

months_list = [january,february,........,december]

for i in range(len(months_list)):
    new_LabelFrame = LabelFrame(root,text= months_list[i].name)
    new_LabelFrame.pack()
    new_label = Label(new_LabelFrame,text ='Name: {}\nDays: {}\nYear: {}'.format(months_list[i].name,months_list[i].days,months_list[i].year))
    new_label.pack()

When i run the code, it geerates a windows with 12 LabelFrame containing only the December's month information. Could you please tell me why?