Why do I keep getting the error "File "TypeError: 'int' object is not callable"?

Question

Hope someone can help explain why I keep getting the following error in Python.

Python version: Python 3.10.4 OS: Windows 11 in a vm

Steps to reproduce the error in REPL or JuyterLab.

def minmax(items):
    return min(items), max(items)
lst = [98, 34, 78, 1, 0, -10, -19, -1]
(min, max) = minmax(lst) # **no error**
min, max = minmax(lst) # **error**. after this point I cannot call minmax without an error
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in minmax
TypeError: 'int' object is not callable
'int' object is not callable

(min, max) = minmax(lst) # **error**
a, b = minmax(lst) # **error**
min, max = minmax(lst) # **error**

restart REPL or restart the kernel in JypterLab will solve the problem. This kind of gives me a hint that the issue might have something to do with the Python binds the variable with an Object.

Request: Whoever takes the time to respond, please also include your thought process. For example, "I have seen this before and before of my experience I know ..." or "I read the Python doc and saw ... which led me to experiment and discover..."

I want to be able to debug these myself and want to understand the thougt process that was used to get to the answer.

What have I tried so far? -REPL to experiment -Jyputer notebook to experiment -read https://careerkarma.com/blog/python-typeerror-int-object-is-not-callable/

Answer 1

In this line:

(min, max) = minmax(lst)

you're assigning integers to min and max. Then, you try to call these integers here:

def minmax(items):
    return min(items), max(items)  # this line

Try this in your interactive console:

>>> min([1, 0, 2])
0
>>> min = 42
>>> min([1, 0, 2])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'int' object is not callable
>>> 

Request: Whoever takes the time to respond, please also include your thought process.

Whenever you see a traceback:

1. Find the line it refers to
2. Try to find all things that could trigger it.

So:

1. The traceback is pointing to this line:

    return min(items), max(items)

2. The traceback says: 'int' object is not callable. This means that you're trying to call an int object. You're only calling min and max on this line, so it must be that min or max are integers. How could it be?
3. You might notice that later, you assign to min and max in your code.