Interesting 'takes exactly 1 argument (2 given)' Python error

Question

For the error:

TypeError: takes exactly 1 argument (2 given)

With the following class method:

def extractAll(tag):
   ...
<         


        

Answer 1

The call

e.extractAll("th")

for a regular method extractAll() is indeed equivalent to

Extractor.extractAll(e, "th")

These two calls are treated the same in all regards, including the error messages you get.

If you don't need to pass the instance to a method, you can use a staticmethod:

@staticmethod
def extractAll(tag):
    ...

which can be called as e.extractAll("th"). But I wonder why this is a method on a class at all if you don't need to access any instance.