<s>[INST] Change one character in a string in Python? What is the easiest way in Python to replace a character in a string like: 
text = "abcdefg";
text[1] = "Z";
           ^

 [/INST] Don't modify strings.
Work with them as lists; turn them into strings only when needed.
>>> s = list("Hello zorld")
>>> s
['H', 'e', 'l', 'l', 'o', ' ', 'z', 'o', 'r', 'l', 'd']
>>> s[6] = 'W'
>>> s
['H', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l', 'd']
>>> "".join(s)
'Hello World'

Python strings are immutable (i.e. they can't be modified).  There are a lot of reasons for this.  Use lists until you have no choice, only then turn them into strings.
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