How do I fix too many values ​​to unpack (expected 2) error?

Question

Python

I am making a translator of the wrong keyboard layout, in the program I need to make it so that when certain buttons are pressed, some variable refers to the list, but when launched it gives an error: too many values ​​to unpack (expected 2)

Here is an excerpt from the program ...

lan1 = []
lan2 = []

but1=Button(root, text="Английский  => Русский", bg = 'grey')
but1.place(x=10, y=285)

Eng = "`qwertyuiop[]asdfghjkl;'zxcvbnm,.~QWERTYUIOP{}ASDFGHJKL:\"ZXCVBNM<>!&?/^@()1234567890-=+\ "
Rus = "ёйцукенгшщзхъфывапролджэячсмитьбюЁЙЦУКЕНГШЩЗХЪФЫВАПРОЛДЖЭЯЧСМИТЬБЮ!?,.:\"()1234567890-=+\ "

def but1_click(event):
    global lan1, lan2
    lan1 = Eng, lan2 = Rus
but1.bind('<Button-1>', but1_click)

Answer 1

lan1 = Eng, lan2 = Rus
Where did you learn this?
Or like this:

lan1 = Eng
lan2 = Rus

Or like this:
lan1, lan2 = Rus, Eng

Answer 2

lan1 = Eng, lan2 = Rus
You can't assign variables like that. And in general, maybe you did something wrong?
You created two lists lan1 and lan2, created two string variables, and then assigned values ​​from Eng and Rus to these lists.
Hence the questions, why make lists if they are not lists, and is such a gap in the form of lan variables necessary? Why not just use Rus/Eng