我试图在django上为我的电影项目添加一个登录功能，并显示此错误：

AttributeError at /signin 'str' object has no attribute 'POST'
这是模板，signin.html

{% extends 'base.html' %}
{% load static %}
{% block content %}
<div class="container">
  <h1>Sign-in</h1>
  <form method="POST" enctype="multipart/form-data">
    {% csrf_token %}
  <div class="mb-3">
    <label class="form-label"></label>
    <input class="form-control" type="text" name="u" placeholder="Enter your username">
    <div class="form-text"></div>
  </div>

  <div class="mb-3">
    <label class="form-label"></label>
    <input class="form-control" type="text" name="p" placeholder="Enter your password">
    <div class="form-text"></div>
  </div>

  <button type="submit" class="btn btn-primary">Submit</button>
  </form>

  {% if messages %}
  {% for i in messages%}
  <ul class='messages'>
    <li>{{i}}</li>
  </ul>
  {% endfor %}
  {% endif %}
</div>

{% endblock %}

路径

from django.urls import path
from movie import views
app_name='movie'
urlpatterns = [
    path('signin',views.signin,name='signin'),
]

views.py

from django.contrib.auth.models import User
from django.contrib.auth import authenticate,login,logout
from django.contrib import messages

def signin(request):
    if(request.method=='POST'):
        u=request.method.POST['u']
        p=request.method.POST['p']
        user=authenticate(username=u,password=p)
        if user:
            login(request,user)
            return home(request)
        else:
            messages.error(request,'Invalid Credentials')
    return render(request,'signin.html')

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