how to tell a variable is iterable but not a string

Question

I have a function that take an argument which can be either a single item or a double item:

def iterable(arg)
    if #arg is an iterable:
        print \"yes         


        

Answer 1

As you point out correctly, a single string is a character sequence.

So the thing you really want to do is to find out what kind of sequence arg is by using isinstance or type(a)==str.

If you want to realize a function that takes a variable amount of parameters, you should do it like this:

def function(*args):
    # args is a tuple
    for arg in args:
        do_something(arg)

function("ff") and function("ff", "ff") will work.

I can't see a scenario where an isiterable() function like yours is needed. It isn't isinstance() that is bad style but situations where you need to use isinstance().