why is Pipeline function used in python code example

Example: whats does pipeline used in pyhton

import math
import os
import random
import re
import sys



if __name__ == '__main__':
    n = int(raw_input().strip())
    
    if (n % 2) == 0 & (2 < n < 6) & (n>20):
        print ("not weird" )
        
    elif (n % 2) == 1 & (6 < n < 20):
        print ("weird")
    
    else :
        print ("weird")