code: def update_extent(self, operation):
          
          #Operations represent continuous lines of code.
          #The last operation to be executed is still the current one.
          line, col = operation.start
          operation.context.module.update_elements(line, col, operation.length,
                                                   operation.docdelta)
docs: Updates the extent of the *module* and its elements using the
          specified operation which has already been executed.