Solution to the puzzle Towering personalities

Here is my solution to the programming puzzle of Towering personalities in python.
This python function takes a list of tuples as its argument.
 Where
    Tuple(n):(height,weight) of nth person

#!/usr/bin/python  
 #This function takes a list of tuples. Tuple(n):(height,weight) of nth person  
 def htower_len(ht_wt):  
   ht_sorted = sorted(ht_wt,reverse=True)  
   wt_sorted = sorted(ht_wt,key=lambda ht_wt:ht_wt[1])  
   max_len = 1   
   len1 = len(ht_sorted)  
   i=0  
   j=0  
   while i < (len1-1):  
     if(ht_sorted[i+1][1] < ht_sorted[0][1]):  
       max_len = max_len+1  
     i=i+1        
   print "maximum tower length :" ,max_len  

I constructed 3 different test cases to test this function.
This above function can be invoked using below test app code, and their results are shown below the function calls:

Test case 1:
htower_len([(5,75),(6.7,83),(4,78),(5.2,90)])
maximum tower length : 3

htower_len([(65, 100),(70, 150),(56, 90),(75, 190),(60, 95),(68, 110)])
maximum tower length : 6

htower_len([(3,2),(5,9),(6,7),(7,8)])  
maximum tower length : 3