Display data with Django - mysql

Question

I'm a beginner at Django and Python.
I'm trying to query a MySQL database.
Entering the data from the admin section works fine. Queering the database doesn't give an error, but it doesn't work.
I tried querying from shell, and it worked perfectly. However, querying from the code section doesn't.
The models.py looks like this:
class Courses(models.Model):
course_title = models.CharField(max_length=200)
course_image = models.ImageField(upload_to='course_images/')
course_duration = models.TimeField()
def __str__(self): return self.course_title
The views.py looks like this;
from django.shortcuts import render
from .models import Courses
def homepage(request):
cos = Courses.objects.all()
context={
'courses': cos
}
return render(request, "main/home.html", context)
The home.html looks like this:
{% for cos in courses %}
{{cos}}
{% endfor %}
I tried using Courses.objects.all and also Courses.objects.all() but it still won't work.
The urls.py looks like this:
from django.urls import path
from . import views
app_name = "main"
urlpatterns = [
path("", views.homepage, name="homepage"),
path('about/', views.about, name='about'),
path('home/', views.home, name'home'),
]
The projects urls.py is:
from django.contrib import admin
from django.urls import path, include
urlpatterns = [ path('admin/', admin.site.urls),
path('', include('main.urls')),
]
I really need some assistance.