from flask import Flask
app=Flask(__name__)

点击Flask同时点击键盘ctrl即可查看Flask的默认初始化函数

def __init__(
        self,
        import_name: str,
        static_url_path: str | None = None,
        static_folder: str | os.PathLike[str] | None = "static",
        static_host: str | None = None,
        host_matching: bool = False,
        subdomain_matching: bool = False,
        template_folder: str | os.PathLike[str] | None = "templates",
        instance_path: str | None = None,
        instance_relative_config: bool = False,
        root_path: str | None = None,
    ):

static 可知默认的静态文件存放地址：

在static文件夹下面新建文件夹images，并导入照片
index.html文件如下：

<img src="{{url_for('static',filename='images/p1.jpg')}}" alt="">

主文件main.py,运行后如下：

from flask import Flask
from flask import render_template
app=Flask(__name__)
@app.route('/')
def index():
    context={
        'strl':'hello'
    }
    return render_template('index1.html')

if __name__=='__main__':
    app.run()

输入网址即可显示图片