```
input_string=mississippi

output_dict={letters=[i,s,p,m],count=[4,4,2,1]}

```

Remove duplicate entries from `input_string` and count those duplicate values and display in descending order.
actual following code remove duplicate entry but how to count the duplicate values

```
def mock(input_string):
    a=list(input_string)
    list1=[]
    for i in a:
        if i not in list1:
            list1.append(i)

    print(list1)           

mock("radffffghhh")  

```