Find Duplicate or Repeating Words in a String Using Python 3

string = "Small brown bug bit a small brown dog on his small brown nose";  
   
#Converts the string into lowercase  
string = string.lower();  
   
#Split the string into words using built-in function  
words = string.split(" ");  
   
print("Duplicate words in a given string : ");  
for i in range(0, len(words)):  
    count = 1;  
    for j in range(i+1, len(words)):  
        if(words[i] == (words[j])):  
            count = count + 1;  
            #Set words[j] to 0 to avoid printing visited word  
            words[j] = "0";  
              
    #Displays the duplicate word if count is greater than 1  
    if(count > 1 and words[i] != "0"):  
        print(words[i]);