Need instruction on how to use isinstance

[Steven W. Orr]

I need to test an argument for a few different types.

I'm calling my function like this

arf = MyFunc(list)

What I want to do is to test for whether something is a string, tuple, list or
function. It's that last one that's causing me a problem.

if isinstance(arg, (str, tuple, list)):

No problem, but there are a lot of types that the type function returns. If I
have a simple function

def foo():
    pass
type(foo)
prints out
<type 'function'>

So, my question is, what value can I use as the 2nd arg to isinstance to see if
foo is a function? And while I'm on the subject, what types does isinstance not
support?

And last, what is the correct way to do it if this is not the right way?

TIA (and hoping I'm clear)

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