Software with best fit algorithm

def best_fit(X, Y):
  xbar = sum(X)/len(X)
  ybar = sum(Y)/len(Y)
  n = len(X)
  numer = sum([xi*yi for xi,yi in zip(X,Y)]) - n * xbar * ybar
  denum = sum([xi**2 for xi in X]) - n * xbar**2
  b = numer / denum
  a = ybar - b * xbar
  print('Best fit line: \ny = {:.2f} + {:.2f}x'.format(a, b))
  
   
X = [2, 4, 6, 8]
Y = [81, 93, 91, 97]

best_fit(X, Y)