code: def deselect_by_visible_text(self, text):
          
          if not self.is_multiple:
              raise NotImplementedError("You may only deselect options of a multi-select")
          matched = False
          xpath = ".//option[normalize-space(.) = %s]" % self._escapeString(text)
          opts = self._el.find_elements(By.XPATH, xpath)
          for opt in opts:
              self._unsetSelected(opt)
              matched = True
          if not matched:
              raise NoSuchElementException("Could not locate element with visible text: %s" % text)
docs: Deselect all options that display text matching the argument. That is, when given "Bar" this
             would deselect an option like:
  
             <option value="foo">Bar</option>
  
             :Args:
              - text - The visible text to match against