flask web 注意事項：
引用靜態文件：url_for('static', filename='style.css')
flask後端通過wtf獲取頁面數據方法：
前端：
<form action="{{ url_for('v_sign')}}" method=post>
{{ form.hidden_tag() }}
後端：
1、
form = SignupForm()
print 'user is %s ' % form.firstname.data
2、
form = SignupForm()
print request.form.get('email')
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flask-sqlalchemy的安裝：
pip install flask_sqlalchemy
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy(app)
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bootstrap的應用.
from flask_bootstrap import Bootstrap
Bootstrap(app)
{% extends "bootstrap/base.html" %}
{% import "bootstrap/wtf.html" as wtf %}
{{ wtf.quick_form(form)}}