code: def _cursor_position_changed(self):
          
          cursor = self._text_edit.textCursor()
          position = cursor.position()
          document = self._text_edit.document()
          char = to_text_string(document.characterAt(position - 1))
          if position <= self._start_position:
              self.hide()
          elif char == ')':
              pos, _ = self._find_parenthesis(position - 1, forward=False)
              if pos == -1:
                  self.hide()
docs: Updates the tip based on user cursor movement.