Python Functions

by | Dec 18, 2021 | Python

def is_prime(n):

    if n == 2:
        return True

    for i in range(2, n):
        if n % i == 0:
            return False
        else:
            continue
    else:
        return True


numbers = [2, 5, 34, 37, 8, 9]

for n in numbers:
    if is_prime(n):
        print("The number ", n, " is a prime number")
    else:
        print("The number ", n, " is not a prime number")

Please note that the function is_prime() returns a boolean value. We are passing an integer as an argument to the function. If the passed number is a prime number, the function is_prime() returns True, and else it returns False.

โ€œnumbersโ€ is a Python list that contains a list of positive integers. We are taking each number from the Python list and calling the is_prime() function with each number. If is_prime(n) returns True, the program prints the number n is a prime number and otherwise, it prints the number is not a prime number.

The program will print the following output:

The number  2  is a prime number
The number  5  is a prime number
The number  34  is not a prime number
The number  37  is a prime number
The number  8  is not a prime number
The number  9  is not a prime number

Now, if we need to check the primality of another number from a different part of the code, we can do so easily using the is_prime() function.

Please note that we pass arguments to a function. And, in the function definition, the passed arguments are called …

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Amrita Mitra

Author

Ms. Amrita Mitra is an author, who has authored the books “Cryptography And Public Key Infrastructure“, “Web Application Vulnerabilities And Prevention“, “A Guide To Cyber Security” and “Phishing: Detection, Analysis And Prevention“. She is also the founder of Asigosec Technologies, the company that owns The Security Buddy.

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