Python String Replace Tutorial

Sometimes you will want to replace occurrences of a substring with a new string, and Python has a built-in method .replace() to achieve it.

Python provides you with the .replace() string method that returns a copy of the string with all the occurrences of old substring replaced with the new substring given as a parameter.

Arguments

It takes three arguments: the substring to replace, the new string to replace it, and an optional number that indicates how many occurrences to replace.

• old − This is the old substring to be replaced.

• new − This is the new substring, which would replace the old substring.

• count − If this optional argument count is given, only the first count occurrences are replaced.

Example of String Replace

In the example code below, you will replace the substring house with car. The method will return a copy with all the house substrings replaced.

Example of String Replace with the Count Optional Argument

In this second example, you specify that you only want two of the occurrences to be replaced. In the below output, you can see that the method returns the string's copy with the first two occurrences of house replaced by car.

Example

Here you will replace the substring isn't for the word is. Then, replace the substring important for the word insignificant, and finally, print out the result contained in the variable movies_antonym.

When we run the above code, it produces the following result:

the rest of the story is insignificant because all it does is serve as a mere backdrop for the two stars to share the screen .

Try it for yourself.

To learn more about Python String Replace, please see this video from our course, Regular Expressions in Python.

This content is taken from DataCamp’s Regular Expressions in Python course by Maria Eugenia Inzaugarat.

Check out our Python String Tutorial.