SimpleFill() returns an error when the input is a complete dataframe

[drkarthi]

This can be a problem if you want to fill missing values for multiple data frames and if some of them turn out to be already complete (have to add an extra check). Returning a warning may be a better option.

[sergeyf]

Good idea. Any interest in a PR that does this?

[drkarthi]

Sure, I can make one.