如何在python-prompt-toolkit中向TextArea添加pageup/pagedown键绑定？

from prompt_toolkit.key_binding import KeyBindings
from prompt_toolkit.keys import Keys
from prompt_toolkit.widgets import TextArea

text_area = TextArea()

kb = KeyBindings()

@kb.add(Keys.PageUp)
def _(event):
    text_area.buffer.cursor_up(count=event.arg)

@kb.add(Keys.PageDown)
def _(event):
    text_area.buffer.cursor_down(count=event.arg)

text_area.accept_handler = kb

from prompt_toolkit.key_binding import KeyBindings
from prompt_toolkit.keys import Keys
from prompt_toolkit.widgets import TextArea

# 创建TextArea实例
text_area = TextArea()

# 创建KeyBindings实例并定义pageup/pagedown键绑定的处理函数
kb = KeyBindings()

@kb.add(Keys.PageUp)
def _(event):
    text_area.buffer.cursor_up(count=event.arg)

@kb.add(Keys.PageDown)
def _(event):
    text_area.buffer.cursor_down(count=event.arg)

# 将KeyBindings实例绑定到TextArea实例
text_area.accept_handler = kb