Number is Prime | Challenge

# Introduction

In mathematics, a prime number is a natural number greater than 1 that is not a product of two smaller natural numbers. For example, 5 is prime because the only ways of writing it as a product, 1 × 5 or 5 × 1, involve 5 itself. However, 4 is not prime because it is a product (2 × 2) in which both numbers are smaller than 4. In this challenge, you need to write a Python function to check if a given number is prime or not.