human
Solve the following python programming problem given the following code:
def distance(a, b) : 
    def _difference(a, b) : 
        if (a > b) : 
            return (a - b) 
else : 
            if (b > a) : 
                return (b - a) 
else : 
                return 0 
assert (len (b) == len (b)) 
    dist = 0 
    for i in range (0, len (a)) : 
        dist += _difference (a [i], b [i]) 
return dist 

    
    

    Fix the buggy line: assert (len (b) == len (b))
assistant
#Here is Python code to fix the buggy line: assert (len (b) == len (b))
.

assert (len (a) == len (b))