Question

how do i replace only one instance of a character in an entire string?

Answer 1

You may accomplish that by converting the string into a list, changing the particular element in the list, and then converting the list back into a string.

Example:
#example string; I want to change the typo at index 6, the character 'a'.
mystring = 'hello aorld'

#I first convert the string into a list of characters.
mystring = mystring.list()

>> mystring
>> ['h','e','l','l','o',' ','a','o','r','l','d' ]

#Now, I change mystring[6] into 'w'.
mystring[6] = 'w'

>>mystring
>>['h','e','l','l','o',' ','w','o','r','l','d' ]

#Then, I convert mystring back into a string.
mystring = ''.join(mystring)

>>mystring
>>'hello world'

Answer 2

This all assumes you know the position of the character in the string you want to change.

Answer 3

There's a typo in my solution.

to convert a string into a list you use:

mystring = list(mystring)

Answer 4

There's another way to accomplish this, but it also assumes you know where the character you want to change is.

This method uses slicing.

mystring = 'hello aorld'

mystring = mystring[:6] + 'w' + mystring[7:]

>>mystring
>>'hello world'

Answer 5

mystring = "hello over there"
newstring = mystring.replace("e","k",1)
print newstring
'hkllo over there'