Dear sir/maddam I am using python Release 2.3.3, but I cant use it solving the following  python source code. Would you please help me in solving the following problem using some other python release. Exponentiation Consider the following Python code: def expo(s,lm,N):  return reduce(lambda x,m: pow(x,m,N),lm,s) def hamming(a):  return a>0 and (a%2)+hamming(a/2) or 0 def htot(k):  n=pow(2,k)  N=pow(2,n)-3  lm=[pow(i,i,N) for i in range(1,n+1)]  lz=[expo(3,lm[:j]+lm[j+1:],N) for j in range(n)]  return sum([hamming(z) for z in lz]) The function htot gives the following result for small values of k: >>>  [htot(i) for i in range(3,8)][35, 122L, 540L, 2068L, 8070L] You are scincerely asked to compute the value of function htot for larger values of k. Go as far as you can.  I am expecting your fast respond.     With Best Regards.     Kalkidan Aweke +251911505062 Addis Ababa Ethiopia