Hackerrank Functions and Modularity 4

Question 1

What will the following code print?
```python
def add(a, b):
    return a + b
result = add(b=3, a=7)
print(result)
```

Accepted Answer

10

Answer

Keyword arguments can be passed in any order; Python maps them by name, so a=7 and b=3 gives 10.

Question 2

Which module provides the `wraps` decorator used to preserve a wrapped function's metadata?

Accepted Answer

functools

Answer

`functools.wraps` copies `__name__`, `__doc__`, and other attributes from the wrapped function to the wrapper.

Question 3

What is the output?
```python
def greet(name, msg='Hello'):
    return f'{msg}, {name}!'
print(greet('Alice', msg='Hi'))
```

Accepted Answer

Hi, Alice!

Answer

Passing `msg='Hi'` overrides the default value 'Hello', so the function returns 'Hi, Alice!'.

Question 4

What does a generator function use instead of `return` to yield values lazily?

Accepted Answer

yield

Answer

The `yield` statement pauses the function and returns a value to the caller, resuming on the next iteration.

Question 5

How do you call a function stored in a variable `fn` with arguments unpacked from a list `args`?

Accepted Answer

fn(*args)

Answer

The `*` operator unpacks a list (or tuple) into positional arguments when calling a function.

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