code: def reverse_dummies(self, X, mapping):
          
          out_cols = X.columns.values.tolist()
          mapped_columns = []
          for switch in mapping:
              col = switch.get('col')
              mod = switch.get('mapping')
              insert_at = out_cols.index(mod.columns[0])
  
              X.insert(insert_at, col, 0)
              positive_indexes = mod.index[mod.index > 0]
              for i in range(positive_indexes.shape[0]):
                  existing_col = mod.columns[i]
                  val = positive_indexes[i]
                  X.loc[X[existing_col] == 1, col] = val
                  mapped_columns.append(existing_col)
              X.drop(mod.columns, axis=1, inplace=True)
              out_cols = X.columns.values.tolist()
  
          return X
docs: Convert dummy variable into numerical variables
  
          Parameters
          ----------
          X : DataFrame
          mapping: list-like
                Contains mappings of column to be transformed to it's new columns and value represented
  
          Returns
          -------
          numerical: DataFrame