How to find prime number in Python in efficient way code example

Example 1: prime number in python

def prime(num):
    if num>1:
        s=int(num/2)
        for i in range(2,s+1):
            if num%i==0:
                return("not prime")
                break
        return("prime")
print(prime(239))

Example 2: prime number program python

# 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