Django模板中的if语句不起作用

我不知道为什么这不起作用。它总是转到{％else％}块。machine_model中的文本类似于“ Lidl-Food Market”或“ Kaufland-Buy Here”或其他没有这两个词的文本。

models.py

from django.db import models
from django.utils import timezone
from django.contrib.auth.models import User
from django import forms
from django.urls import reverse


class MyName(models.Model):
    name = models.CharField(max_length=50, unique=True)

    def __str__(self):
        return self.name

class MyModel(models.Model):
    name = models.CharField(max_length=50, unique=True)

    def __str__(self):
        return self.name

class MySide(models.Model):
    name = models.CharField(max_length=50, unique=True)


class MyMachine(models.Model):
    date_delivery = models.DateTimeField(null=True)
    machine_name = models.ForeignKey(MyName, on_delete=models.PROTECT)
    machine_model = models.ForeignKey(MyModel, on_delete=models.PROTECT)
    machine_serial = models.CharField(max_length=15, default='0')
    use_side = models.ForeignKey(MySide, on_delete=models.PROTECT)

views.py

from django.views.generic import ListView
from .models import MyMachine

class MyMachineListView(ListView):
    model = MyMachine
    template_name = 'site/home.html'
    context_object_name = 'machines'
    ordering = ['date_delivery']

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        site_title = 'Home'
        context["site_title"] = site_title
        return context

home.html

{% extends "site/base.html" %}
{% load static %}
{% block content %}
    {% for machine in machines %}
            <article class="media content-section">
                <div class="media-body">
                    <div class="article-metadata">
                        <small class="text-muted">{{ machine.date_delivery|date:"d.F Y" }} 
                        </small>  
                    </div>
                        <h2><a class="article-title" href="">{{ machine.machine_name }} - {{ machine.machine_serial }}</a></h2>

                        {% if 'Lidl' in machines.machine_model %}
                            <p class="article-content">{{ machine.use_side }} - Lidl</p>
                        {% elif 'Kaufland' in machines.machine_model %}
                            <p class="article-content">{{ machine.use_side }} - Kaufland</p>
                        {% else %}
                            <p class="article-content">{{ machine.use_side }} - {{ machine.machine_model}}</p>
                        {% endif %}

                </div>
            </article>
    {% endfor %}
{% endblock content %}

其他一切都很好。先感谢您！