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Python Introducing Lists Meet Lists All You Need Is Lists

Chandler Pettibone
Chandler Pettibone
2,191 Points

AttributeError: 'list' object attribute 'extend' is read-only

So I am super confused why I am getting the Attribute Error that extend is read only. In the video before the challenge we added James and Guil to the attendees using attendees.extend. However, when I did beatles.extend = others and listing the others out, the computer wasn't happy.

Thanks for the help!

beatles = ["John"]
others = ["George", "Ringo"]
# Your code here
beatles.extend = others

1 Answer

Eric M
Eric M
11,545 Points

Hi Chandler,

You're pretty close!

.extend takes an argument the same way as .append, it doesn't take its argument via the assignment operator (equals sign, =)

That should be all you need