如何在flask-WTF &wtforms的字符串字段中输入新行/多行

from flask import Flask, render_template
from flask_wtf import FlaskForm
from wtforms import TextAreaField, SubmitField

class MyForm(FlaskForm):
    my_text = TextAreaField('My Text')
    submit = SubmitField('Submit')

@app.route('/', methods=['GET', 'POST'])
def index():
    form = MyForm()
    if form.validate_on_submit():
        # 处理表单提交的数据
        my_text = form.my_text.data
        # 其他逻辑处理...
    return render_template('index.html', form=form)

<form method="POST" action="/">
  {{ form.hidden_tag() }}
  {{ form.my_text.label }}
  {{ form.my_text(class="form-control") }}
  {{ form.submit(class="btn btn-primary") }}
</form>