Python Remove last 3 characters of a string

I'm trying to remove the last 3 characters from a string in python, I don't know what these characters are so I can't use rstrip, I also need to remove any white space and convert to upper-case

an example would be:

foo = "Bs12 3ab"
foo.replace(" ", "").rstrip(foo[-3:]).upper()

This works and gives me BS12 which is what I want, however if the last 4th & 3rd characters are the same I loose both eg if foo = "BS11 1AA" I just get 'BS'

examples of foo could be:

BS1 1AB
bs11ab
BS111ab

The string could be 6 or 7 characters and I need to drop the last 3 (assuming no white space)

Any tips?

Solution 1:

Removing any and all whitespace:

foo = ''.join(foo.split())

Removing last three characters:

foo = foo[:-3]

Converting to capital letters:

foo = foo.upper()

All of that code in one line:

foo = ''.join(foo.split())[:-3].upper()

Solution 2:

It doesn't work as you expect because strip is character based. You need to do this instead:

foo = foo.replace(' ', '')[:-3].upper()

Solution 3:

>>> foo = "Bs12 3ab"
>>> foo[:-3]
'Bs12 '
>>> foo[:-3].strip()
'Bs12'
>>> foo[:-3].strip().replace(" ","")
'Bs12'
>>> foo[:-3].strip().replace(" ","").upper()
'BS12'

Solution 4:

You might have misunderstood rstrip slightly, it strips not a string but any character in the string you specify.

Like this:

>>> text = "xxxxcbaabc"
>>> text.rstrip("abc")
'xxxx'

So instead, just use

text = text[:-3] 

(after replacing whitespace with nothing)