SettingWithCopyWarning: A value is trying to be set on a copy of a slice from a DataFrame

This is a warning message in pandas that appears when a new value is assigned to a slice of a DataFrame, but the slice is actually a copy of the original DataFrame. This can lead to unexpected behavior or errors.

The warning message is meant to remind the user to be careful when modifying a slice, as it may not affect the original DataFrame as intended.

To avoid this warning, it is recommended to use the .loc indexer to explicitly select the rows and columns to modify. This ensures that the slice is a view of the original DataFrame, not a copy.

For example:

df.loc[row_indexer, col_indexer] = value

Alternatively, you can also use .copy() to create a copy of the DataFrame, and then modify the copy without affecting the original DataFrame.