Python error explained
TypeError: what it means and how to fix it
You tried to join text and a number with +.
The message
TypeError: can only concatenate str (not "int") to strWhat it means
+ joins two strings or adds two numbers, but Python will not guess what you mean when one side is text and the other is a number. You have to convert one of them first.
Common causes
- Building a message with + and a number
- Adding to a value that came from input(), which is always text
- Reading numbers from a file without converting them
Example that raises it
age = 30
print("Next year you will be " + age + 1)
The fix
age = 30
print(f"Next year you will be {age + 1}")
Tip: f-strings convert numbers for you, so f"{age}" is the easiest fix. Use int() or float() when you need to do maths on text from input().
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