Django Crispy表单:设置文本区的行

from django import forms
from crispy_forms.helper import FormHelper
from crispy_forms.layout import Layout, Field

class MyForm(forms.Form):
    my_textarea = forms.CharField(widget=forms.Textarea(attrs={'rows': 5}))

    def __init__(self, *args, **kwargs):
        super(MyForm, self).__init__(*args, **kwargs)
        self.helper = FormHelper()
        self.helper.layout = Layout(
            Field('my_textarea')
        )