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1. What does this program print when show(42) runs? ``

python
def show(value):
    if isinstance(value, str):
        text = value
    print("after if:", text)


show(42)

``

after if: 42after if: NoneUnboundLocalError: text has no value, because the assignment did not run for 42NameError: text is not defined

2. Why does isinstance(value, list[str]) raise TypeError, even though list[str] is valid Python? ``

python
value = ["a", "b"]
print(isinstance(value, list[str]))

``

list is not a real Python type, so Python cannot find itisinstance checks only the outer type, so Python refuses a type with brackets because it cannot check the items insidePython removes the items from the type when the program runs, so it cannot check themisinstance only works with str and int

3. What does this program print? ``

python
def describe(value):
    match value:
        case str() as text:
            return f"string {len(text)}"
        case int() as number:
            return f"int {number * 2}"
    return f"other {value}"


print(describe(21))
print(describe(None))

``

int 42, then other Noneint 21, then other Noneother 21, then other Noneint 42, then nothing

4. What does this code print? ``

python
value = None
if isinstance(value, str) and value.strip() == "":
    print("blank")
else:
    print("no match")

``

blankno matchAttributeErrornothing is printed

5. The line case str() as text: checks a type and names the value in one step. Python calls this kind of check a ___.

Type your answer.

Pattern matching and the walrus operator