code: def select_line(self):
          
          self.cursor.movePosition(self.cursor.StartOfBlock)
          text = self.cursor.block().text()
          lindent = len(text) - len(text.lstrip())
          self.cursor.setPosition(self.cursor.block().position() + lindent)
          self.cursor.movePosition(self.cursor.EndOfBlock,
                                   self.cursor.KeepAnchor)
docs: Select the entire line but starts at the first non whitespace character
          and stops at the non-whitespace character.
          :return: