ImportError: No module named 'decouple' wh

I was trying to deploy my django project on heroku from heroku cli. So I created an app and then I ran git push heroku master from the project directory. Then I got the errors:

remote: -----> $ python manage.py collectstatic --noinput 
remote:      Traceback (most recent call last): 
remote:          File "manage.py", line 15, in <module> 
remote:            execute_from_command_line(sys.argv) 
remote:          File "/app/.heroku/python/lib/python3.5/site-packages/django/core/management/__init__.py", line 371, in execute_from_command_line 
remote:            utility.execute() 
remote:          File "/app/.heroku/python/lib/python3.5/site-packages/django/core/management/__init__.py", line 317, in execute 
remote:            settings.INSTALLED_APPS 
remote:          File "/app/.heroku/python/lib/python3.5/site-packages/django/conf/__init__.py", line 56, in __getattr__ 
remote:            self._setup(name) 
remote:   File "/app/.heroku/python/lib/python3.5/site-packages/django/conf/__init__.py", line 43, in _setup remote:            self._wrapped = Settings(settings_module) 
remote:          File "/app/.heroku/python/lib/python3.5/site-packages/django/conf/__init__.py", line 106, in __init__ 
remote:            mod = importlib.import_module(self.SETTINGS_MODULE) 
remote:          File "/app/.heroku/python/lib/python3.5/importlib/__init__.py", line 126, in import_module 
remote:            return _bootstrap._gcd_import(name[level:], package, level) 
remote:          File "<frozen importlib._bootstrap>", line 986, in _gcd_import 
remote: File "<frozen importlib._bootstrap>", line 969, in _find_and_load 
remote:          File "<frozen importlib._bootstrap>", line 958, in
_find_and_load_unlocked 
remote:          File "<frozen importlib._bootstrap>", line 673, in _load_unlocked 
remote:          File "<frozen importlib._bootstrap_external>", line 665, in exec_module 
remote:          File "<frozen importlib._bootstrap>", line 222, in _call_with_frames_removed 
remote:          File "/tmp/build_93c58c906371cd0110470b6bb3ccecc1/funderpreneur/settings.py", line 15, in <module> 
remote:            from decouple import Csv, config 
remote:        ImportError: No module named 'decouple' 
remote:  
remote:  !     Error while running '$ python manage.py collectstatic --noinput'. 
remote:        See traceback above for details. 
remote:  
remote:        You may need to update application code to resolve this error. 
remote:        Or, you can disable collectstatic for this application: remote:  
remote:           $ heroku config:set DISABLE_COLLECTSTATIC=1 
remote:  
remote:        https://devcenter.heroku.com/articles/django-assets 
remote:  !     Push rejected, failed to compile Python app. 
remote:  
remote:  !     Push failed

So as it is mentioned, I ran heroku config:set DISABLE_COLLECTSTATIC=1. Then the codes were pushed in the repository. Then I ran heroku run python3 manage.py migrate. But still I got the same error saying:

File "/app/funderpreneur/settings.py", line 15, in

from decouple import Csv, config ImportError: No module named 'decouple'

But I have python-decouple installed locally for both python 2 and 3. And also the whole project is running on django version 2 and python version 3.5.2. But in the runtime.txt I have set python-3.6.4. I have requirements.txt where decouple is already there.

In my settings.py I had

import django_heroku
django_heroku.settings(locals())

But I was getting errors so I commented them. Still getting error.

What is wrong or what am I doing wrong?

Edit

My requirements.txt:

dj-database-url
django
gunicorn
psycopg2
whitenoise
dj-static
Unipath
python-decouple
Pillow
Markdown
bleach
python-decouple
django-material
raven
django-debug-toolbar
django-tables2
django-phonenumber-field
django-guardian
django-notifications-hq
djangorestframework
matplotlib
numpy
seaborn
pandas
django-heroku

And the strucutre is:

.
├── core
│   ├── admin.py
│   ├── apps.py
│   ├── __init__.py
│   ├── migrations
│   │   ├── __init__.py
│   │   └── __pycache__
│   │       └── __init__.cpython-35.pyc
│   ├── models.py
│   ├── __pycache__
│   │   ├── admin.cpython-35.pyc
│   │   ├── __init__.cpython-35.pyc
│   │   ├── models.cpython-35.pyc
│   │   └── views.cpython-35.pyc
│   ├── templates
│   │   └── core
│   │       ├── base.html
│   │       ├── footer.html
│   │       ├── index.html
│   │       ├── login.html
│   │       ├── navbar.html
│   │       ├── nav.html
│   │       ├── partial_settings_menu.html
│   │       ├── password.html
│   │       ├── picture.html
│   │       ├── profile.html
│   │       └── registration.html
│   ├── tests.py
│   ├── urls.py
│   └── views.py
├── db.sqlite3
├── funderpreneur
│   ├── fonts
│   │   ├── material-design-icons
│   │   │   ├── Material-Design-Iconsd41d.eot
│   │   │   ├── Material-Design-Icons.svg
│   │   │   ├── Material-Design-Icons.ttf
│   │   │   └── Material-Design-Icons.woff
│   │   └── roboto
│   │       ├── Roboto-Bold.ttf
│   │       ├── Roboto-Bold.woff
│   │       ├── Roboto-Light.ttf
│   │       ├── Roboto-Light.woff
│   │       ├── Roboto-Medium.ttf
│   │       ├── Roboto-Medium.woff
│   │       ├── Roboto-Regular.ttf
│   │       ├── Roboto-Regular.woff
│   │       ├── Roboto-Thin.ttf
│   │       └── Roboto-Thin.woff
│   ├── __init__.py
│   ├── __pycache__
│   │   ├── __init__.cpython-35.pyc
│   │   ├── settings.cpython-35.pyc
│   │   ├── urls.cpython-35.pyc
│   │   └── wsgi.cpython-35.pyc
│   ├── settings.py
│   ├── static
│   │   ├── css
│   │   │   ├── account-settings.css
│   │   │   ├── bootstrap.min.css
│   │   │   ├── custom-materialize.css
│   │   │   ├── footer.css
│   │   │   ├── high-rise-building.jpg
│   │   │   ├── materialize.css
│   │   │   ├── navbar.css
│   │   │   ├── navbar-top-fixed.css
│   │   │   ├── style2.css
│   │   │   └── style.css
│   │   ├── humans.txt
│   │   ├── img
│   │   │   └── buet_logo.png
│   │   └── js
│   │       ├── bootstrap.min.js
│   │       ├── circular-progress-jquery.js
│   │       ├── jquery-1.11.2.min.js
│   │       ├── jquery-slim.min.js
│   │       ├── jquery.waypoints.min.js
│   │       ├── materialize.js
│   │       ├── popper.min.js
│   │       ├── profile-validation.js
│   │       └── registration-validation.js
│   ├── urls.py
│   └── wsgi.py
├── manage.py
├── media
├── Pipfile
├── Procfile
├── README.md
├── requirements.txt
├── runtime.txt
└── staticfiles

回答1:

I think you haven't written packages name from requirements.txt to the Pipfile bellow [packages] section. You should add packages in this format-