TypeError 'str' Object Does Not Support Item Assignment
Evan Hicks
—The Problem
When you run the code below, Python will throw the runtime exception TypeError: 'str' object does not support item assignment.
text = "hello world" if text[0].islower(): text[0] = text[0].upper()
This happens because in Python strings are immutable, and can’t be changed in place.
The Solution
The solution is to use one of Python’s built in functions for string manipulation. In this particular case, capitalize() is what you’ll need.
text = "hello world" text = text.capitalize()
Note that capitalize creates a new string and returns that new string. That’s why we have to assign that new string to the text variable. In the example below, text would remain unchanged, and capital would have the result of capitalizing the text variable.
text = "hello world" capital = text.capitalize()
Further Reading
If you’re looking to get a deeper understanding of how Python application monitoring works, take a look at the following articles:
- Sentry BlogPython Performance Testing: A Comprehensive Guide
- Syntax.fmListen to the Syntax Podcast
- Sentry BlogLogging in Python: A Developer’s Guide
- Listen to the Syntax Podcast
![Syntax.fm logo]()
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