![python - How to lowercase a pandas dataframe string column if it has missing values? - Stack Overflow python - How to lowercase a pandas dataframe string column if it has missing values? - Stack Overflow](https://i.stack.imgur.com/XHZbN.png)
python - How to lowercase a pandas dataframe string column if it has missing values? - Stack Overflow
When I am checking equality of two strings, is it faster to convert both strings to uppercase first or to convert to lowercase? Does the equality check run faster with uppercase or
![How to convert Upper case into Lowercase letter and vice versa in python || python tutorial #12 - YouTube How to convert Upper case into Lowercase letter and vice versa in python || python tutorial #12 - YouTube](https://i.ytimg.com/vi/onm_oSJ10V0/maxresdefault.jpg)