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from numpy import array, bitwise_or
from itertools import combinations, chain 

n,k=map(int,input().split())
arr=list(map(int,input().split()))
tup=map(list,chain.from_iterable(map(lambda x:combinations(arr,x),range(1,k+1)))) 
ans=map(lambda x:bitwise_or.reduce(array(x,dtype='int')),tup)
print(len(set(ans)))

n is the number of elements in set
the code makes subsets of size <= k and performs bitwise or on each subset and prints the number of unique elements formed

Do you know what part is slow? If not, you might want to try profiling it.