Columns / names

col(name, *more_names)	Return an expression representing column(s) in a dataframe.
Expr.alias(name)	Rename the expression.
Expr.exclude(columns, *more_columns)	Exclude columns from a multi-column expression.
Expr.keep_name()	Keep the original root name of the expression.
Expr.map_alias(function)	Rename the output of an expression by mapping a function over the root name.
Expr.prefix(prefix)	Add a prefix to the root column name of the expression.
Expr.suffix(suffix)	Add a suffix to the root column name of the expression.