def set_col_width(self, col, new_width):
self._grid.set_col_width(col, new_width)<EOL>self._repack()<EOL>
Set the width of the given column.  You can provide the width as an 
integer or the string 'expand'.

If you provide an integer, the column will be that many pixels wide, so 
long as all the cells in that column fit in that space.  If the cells 
don't fit, the column will be just wide enough to fit them.  It is 
common to specify a width of "0" to make the column as narrow as 
possible.

If you provide the string 'expand', the column will grow to take up any 
extra space allocated to the grid but not used by any of the other 
columns.  If multiple columns are set the expand, the extra space will 
be divided evenly between them.