python code for prime numbers

# Time Efficient Primality Check in Python

def primeCheck(n):
    # 0, 1, even numbers greater than 2 are NOT PRIME
    if n==1 or n==0 or (n % 2 == 0 and n > 2):
        return "Not prime"
    else:
        # Not prime if divisable by another number less
        # or equal to the square root of itself.
        # n**(1/2) returns square root of n
        for i in range(3, int(n**(1/2))+1, 2):
            if n%i == 0:
                return "Not prime"
        return "Prime"

# effiecent and fast way to generate prime numbers
def primeCheck(n):
    if n == 1 or n == 0 or (n % 2 == 0 and n > 2):
        return False
    else:
        for o in range(3, int(n ** (1 / 2)) + 1, 2):
            if n % o == 0:
                return False
        return True


for a in range(2**15):
    if primeCheck(a):
        prime_numbers.append(a)

def prime(num):
        for x in range(2,num):
            if num % x == 0:
                return False
        return True

#function that check if ur number is a prime number in one line code
def is_prime(number): return not(bool([True for i in range(2, number//2) if number % i == 0 ]))

#for exmple 
print(is_prime(42))
print(is_prime(43))

n = 20
primes = []

for i in range(2, n + 1):
	for j in range(2, int(i ** 0.5) + 1):
 		if i%j == 0:
 			break
	else:
		primes.append(i)

print(primes)

#make the function
#to do this all hte vairibles go in side the function

def CheckIfPrime ():
    a1 = input("which number do you want to check")
    a = int(a1)#you need the checking number as an int not an str
    b = 2 #the number to check againts
    c = ("yes")
    while b < a:#run the loop
        if a%b == 0:#check if the division has a remainder
            c = ("no")#set the answer
        b = b+1
    print(c)#print the output
CheckIfPrime ()#call the function