在基模板中放置favicon.ico图标

 {% extends "bootstrap/base.html" %}

{% block title %}Flasky{% endblock %}
################################################################
{% block head %}
{{ super() }}
<link rel="shortcut icon" href="{{ url_for("static", filename="favicon.ico") }}" type="image/x-icon">
<link rel="icon" href="{{ url_for("static", filename="favicon.ico") }}" type="image/x-icon">
{% endblock %}
################################################################
{% block navbar %}
<div class="navbar navbar-inverse" role="navigation">
    <div class="container">
        <div class="navbar-header">
            <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
                <span class="sr-only">Toggle navigation</span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
            </button>
            <a class="navbar-brand" href="/">Flasky</a>
        </div>
        <div class="navbar-collapse collapse">
            <ul class="nav navbar-nav">
                <li><a href="/">Home</a></li>
            </ul>
        </div>
    </div>
</div>
{% endblock %}

{% block content %}
<div class="container">
    {% block page_content %}{% endblock %}
</div>
{% endblock %}

一.使用super（）保留bootstrap/base.html基模板中定义的块的原始内容
二.图标的声明会插入head块的末尾。
重要，研究bootstrap/base.html基模板中定义的各个块的内容以及如何插入。