text: Title: [BUG] Error message on "new column names" is incorrect in deconcatenate_columns
  Body: # Brief Description
  
  If I pass in the wrong number of column names in deconcatenate_columns, the error message simply reflects back the number of columns that I provided, rather than the number of columns I need to provide.
  
  Specifically, these two lines need to be changed:
  
  ```python
  -> 1033             f"you need to provide {len(new_column_names)} names"
     1034             "to new_column_names"
  ```
  
  to:
  
  ```python
  -> 1033             f"you need to provide {len(deconcat.shape[1])} names "
     1034             "to new_column_names"
  ```
  
  (Extra space needed at the end of the first line as well.)