Create a compress function in Python?

Question

I need to create a function called compress that compresses a string by replacing any repeated letters with a letter and number. My function should return the shortened vers

Answer 1

string = 'aabccccd' output = '2a3b4c4d'

new_string = " "
count = 1
for i in range(len(string)-1):
    if string[i] == string[i+1]:
        count = count + 1
    else:         
        new_string =  new_string + str(count) + string[i]
        count = 1 
new_string = new_string + str(count) + string[i+1]    
print(new_string)