Hackerrank Functions and Modularity 2

Question 1

What does the `*args` parameter in a Python function allow?

Accepted Answer

Passing a variable number of positional arguments

Answer

`*args` collects extra positional arguments into a tuple, allowing functions to accept any number of positional inputs.

Question 2

Which statement correctly imports only the `sqrt` function from the `math` module?

Accepted Answer

from math import sqrt

Answer

`from math import sqrt` selectively imports just the `sqrt` name into the current namespace.

Question 3

What is the output of the following code?
```python
def f(x, y=10):
    return x + y
print(f(5))
```

Accepted Answer

15

Answer

Since `y` defaults to 10 and only `x=5` is passed, the function returns 5 + 10 = 15.

Question 4

What does `__name__ == '__main__'` check for in a Python module?

Accepted Answer

Whether the script is being run directly (not imported)

Answer

When a script is run directly, Python sets `__name__` to `'__main__'`; when imported, it's set to the module's name.

Question 5

What is a closure in Python?

Accepted Answer

A nested function that captures variables from its enclosing scope

Answer

A closure is a nested function that retains access to variables from its enclosing function even after that function has returned.

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