This function converts labelled class vectors
into a generic data format, which means that simply all labelled
class attributes will be removed, so all vectors / variables will most
likely become atomic. Additionally, tbl_df and
tbl class attributes will be removed from data frames, and
a lbl_df class attribute will be added. See 'Note'.
unlabel(x)A data frame, which contains labelled class
vectors or a single vector of class labelled.
A data frame or single vector (depending on x) with common object classes.