def remove_duplicate(string):
  from collections import OrderedDict
  
  result = ' '.join(OrderedDict((w,w) for w in string.split()).keys())
  return result
def is_not_prime(n):
    import math
    
    result = False
    for i in range(2,int(math.sqrt(n)) + 1):
        if n % i == 0:
            result = True
    return result