You cannot!

Strings in Python are immutable (something that cannot be changed)

Why are Python strings immutable?

Readhere

What can you do?

You can create a new modified string.

Examples

Convert all characters to upper case

original="My String"new_string=original.upper()print(new_string)# "MY STRING"

Change one character

Since you can't really change the string, the solution is to convert it a mutable type likelist and modify that.

original="My String"original_list=list(original)original_list[0]='m'new_string="".join(original_list)print(new_string)# 'my String'

You could also try slicing to speed up the process