Returning the first N characters of a unicode string

I have a string in unicode and I need to return the first N characters. I am doing this:

result = unistring[:5]

but of course the length of unicode strings != length of characters. Any ideas? The only solution is using re?

Edit: More info

unistring = "Μεταλλικα" #Metallica written in Greek letters
result = unistring[:1]

returns-> ?

I think that unicode strings are two bytes (char), that's why this thing happens. If I do:

result = unistring[:2]

I get

M

which is correct, So, should I always slice*2 or should I convert to something?