Control flow is a fundamental concept in any programming language, including Rust. The if-else statement is a basic control flow construct that allows you to execute different code blocks based on certain conditions.

In this challenge, you will write a function is_even(n: i32) -> bool that checks if a given number is even or odd using an if-else statement. The function should return true if the number is even, and false if it is odd.

• The function should take an integer as input.
• Use an if-else statement to determine if the number is even.
• Return true if the number is even.
• Return false if the number is odd.

assert_eq!(is_even(4), true);
assert_eq!(is_even(7), false);
assert_eq!(is_even(0), true);
assert_eq!(is_even(-2), true);
assert_eq!(is_even(-3), false);