Python SyntaxError: '（' (U+FF08) Invalid Character

In your code, you are using an invalid character '（' (U+FF08), which looks like a left parenthesis but is actually a full-width character. Python only accepts half-width parentheses as valid syntax.

To resolve this issue, you need to replace the character with a half-width parenthesis:

citySalary = data.groupby('city')['average'].mean().sort_values(ascending=False)

This will fix the syntax error in your code.