python prime number

                                    Credit to: https://www.programiz.com/python-programming/examples/prime-number
# get all prime numbers smaller than 1000
for num in range(0,1000):
  if num > 1:
     # check for factors
     for i in range(2,num):
         if (num % i) == 0:
             print(num,"is not a prime number")
             print(i,"times",num//i,"is",num)
             break
     else:
         print(num,"is a prime number")

  # if input number is less than
  # or equal to 1, it is not prime
  else:
     print(num,"is not a prime number")

                                    import math
a=[i for i in range(2,int(input('prime number range'))) if 0 not in [i%n for n in range(2,int(math.sqrt(i)))]]
print(a)

                                    # 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"

                                    # Python program to display all the prime numbers within an interval

lower = 900
upper = 1000

print("Prime numbers between", lower, "and", upper, "are:")

for num in range(lower, upper + 1):
   # all prime numbers are greater than 1
   if num > 1:
       for i in range(2, num):
           if (num % i) == 0:
               break
       else:
           print(num)Copied

                                    until = 20
[n for n in range(2, until) if all(n % m != 0 for m in range(2, n-1))]