How to increment index in Python loop

Question

I am wanting to loop through a string and capture 2 items each time while also incrementing through the index of the iterable. So I want to slice 2 items but increase the index by 1 every time through the loop. How can I do this?

my_string = 'teststring'

desired output = te es st ts st tr ri in ng

I have tried the following to slice the two items, but can't figure out the best way to iterate thought the index

str1 = 'teststring'
i=0
while i<10: 
    i +=1
    str2=str1[0:2]
    print(str2)

Answer 1

By using list comprehension you can do this in a one-liner

s = 'teststring'

r = ' '.join([s[i:i+2] for i in range(len(s)-1)])

print(r)