# 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"

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