code: def remove_col_label(self, event):#, include_pmag=True):
          
          er_possible_headers = self.grid_headers[self.grid_type]['er'][2]
          pmag_possible_headers = self.grid_headers[self.grid_type]['pmag'][2]
          er_actual_headers = self.grid_headers[self.grid_type]['er'][0]
          pmag_actual_headers = self.grid_headers[self.grid_type]['pmag'][0]
          col = event.GetCol()
          label = self.grid.GetColLabelValue(col)
          if '**' in label:
              label = label.strip('**')
          if label in self.grid_headers[self.grid_type]['er'][1]:
              pw.simple_warning("That header is required, and cannot be removed")
              return False
          #elif include_pmag and label in self.grid_headers[self.grid_type]['pmag'][1]:
          #    pw.simple_warning("That header is required, and cannot be removed")
          #    return False
          else:
              print('That header is not required:', label)
              self.grid.remove_col(col)
              #if label in er_possible_headers:
              try:
                  print('removing {} from er_actual_headers'.format(label))
                  er_actual_headers.remove(label)
              except ValueError:
                  pass
              #if label in pmag_possible_headers:
              try:
                  pmag_actual_headers.remove(label)
              except ValueError:
                  pass
          # causes resize on each column header delete
          # can leave this out if we want.....
          self.main_sizer.Fit(self)
docs: check to see if column is required
          if it is not, delete it from grid