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No module named scipy even though it is installed

I am trying to use scipy but when I import it with import scipy, it says "no module named scipy. I have used pip list to see if it is installed and it is, and i have tried pip install scipy but it just said that it was already installed. Does anyone know how to fix this?
SOLVED: ran the code with python3 instead of python

it is possible you have 2 versions of python installed, python2.7 or python3.x .. when you install stuff with pip and want to use it for a specific python version:
pip install scipy is for python 2.7, so its "python" in the terminal and "python x" to run scripts
pip3 install scipy is for python 3, so its "python3" in the terminal and "python3 x" to run scripts
in your case, you would be calling scripts like:
python pythonFile.py
you would be installing packages like:
pip install package
and you would be using python in the terminal with "python"
if that still doesn't work, for me solving that problem was updating numpy. not sure if it would be the same with you. hope this helped

Pip inside virtual environment throws error

I am using virtual environment in python. When I use pip list command or any command to install packages it throws an error.
from pip._internal.distributions import (
ModuleNotFoundError: No module named 'pip._internal.distributions'
When I check the version pip -V inside venv it shows the version of pip (i.e. no error, working great). But, it is not working in any other commands. Please ask if I did not make it clear.
Thank you!!!
EDIT:-
I am using Windows 10 Pro. I installed python from their official website of version 3.8.1 using the windows installer. And, my pip version is 20.0.2 I installed pip by adding get-pip.py in bin file. I think there should not be any problem.

Pillow is installed, but still getting "ImportError: No module named PIL"

I did find this question asked by few more people, but none of those exactly met my situation, so asking here myself.
I've (rather had) two versions of Python (2.7 and 3.4.3) on my Mac running the latest MacOS High Sierra. As I understand, the v2.7 comes as default installation with the MacOS. And I installed the 3.4.3 (from .dmg file downloaded from the python site). Thus now, the python command defaults to the 2.7, while python3 points to the 3.4.3 in the terminal.
While trying to learn, I tried a python script that uses
import PIL and from PIL import Image
But when running, this gave the error ImportError: No module named PIL.
Upon research on google, I figured out to install PIL and Pillow using
sudo pip install Pillow
It installed correctly, but I'm still getting the same error.
To remove the confusion, I decided to remove the python 3.4.3 from the system. But even after it's removed, I still get the same error.
Even pip list displays Pillow 5.1.0 alright.
So right now, I've only Python 2.7, and the error persists, while Pillow is also in there.
which python gives /opt/local/bin/python as the path.
Does any of the above ring a bell? Any ideas, what else could be missing here?

Phew, finally found the issue. Thanks #Yash for the pointers.
Incidentally I did a which -a python and surprisingly got this output:
/opt/local/bin/python
/usr/bin/python
Damn, I don't remember when I installed a second 2.7 version on the /opt/local/bin folder (probably via macports). Alright, removed the confusion, deleted this python, so now I'm left only with the system installed python at /usr/bin.
And now the imports all run perfectly fine as expected. :-)

Try this,
sudo pip install image
I hope it works! One more thing, do check if you're running python3 filename.py instead of python filename.py, if you want to install it for Python 3, run the command,
sudo pip3 install Pillow

Basic Installation:
pip install Pillow
Windows Installation:
pip install Pillow
Reference: https://pillow.readthedocs.io/en/stable/installation.html

Try this. It worked for me
pip install --upgrade --force-reinstall pillow
If you get something like access denied error run the below command
pip install --upgrade --force-reinstall pillow --user

Installing OpenMDAO

I am trying to install OpenMDAO, which is an open source framework that uses python. So before I get to it, it needs 3 packages:
Fortran Compiler
NumPY
ScyPy
Which I did install using homebrew:
brew install gfortran
sudo easy_install-2.6 pip
sudo pip-2.6 install numpy
sudo pip-2.6 install scipy
Now, to install OpenMDAO, I'm supposed to be in the OpenMDAO folder and at that level I should run this script:
python go-openmdao-dev.py
But I keep getting this error:
ERROR: the following prerequisites could not be imported: ['scipy'].
So I was talking to the people at OpenMDAO, and it seems that I need to use is python2.6 - although I'm not certain, so my guess is that all the packages I installed are for python 2.7 which I downloaded since it was recommended in the python website.
The one that comes with Mac was not. So when I type in terminal the following:
python2.6
It actually runs that version. So at this point I don't know if I have to go run the script in python 2.6, but if so, I have no idea how to do it. I tried doing this and it did not work:
If anyone is familiar with the environment or just with python itself and has any suggestions, I'll really appreciate it.

This question was answered on the OpenMDAO support forum:
http://openmdao.org/forum/questions/744/error-the-following-prerequisites-could-not-be-imported-scipy
The solution was to install scipy and numpy for python2.7. The original poster first installed them for python2.6, but then ran the go-openmdao.py script with python2.7. Once all the pre-reqs were installed for 2.7, it worked.

I had the same problem after downloading scipy from a .dmg. I uninstalled, and then reinstalled from source: http://sourceforge.net/projects/scipy/files/scipy/0.12.0/ and then the openmdao installer recognized scipy.
This may be useful (from INSTALL.txt in scipy-0.12.0.tar.gz):
To test SciPy after installation (highly recommended), execute in
Python
>>> import scipy
>>> scipy.test()
To run the full test suite use
>>> scipy.test('full')
Please note that you must have version 0.10 or later of the 'nose'
test framework installed in order to run the tests. More information
about nose is available on the website__.
__ http://somethingaboutorange.com/mrl/projects/nose/

Installing numpy on Red Hat 6?

I'm trying to install numpy on a Red Hat (RHEL6) 64-bit linux machine that has Python 2.7. I downloaded and untar'd numpy 1.6.2 from Sourceforge, and I did the following commands in the numpy-1.6.2 folder:
python ./setup.py build
sudo python ./setup.py install #without sudo, this gives a permissions error.
Then, when I do import numpy on the Python prompt, I get ImportError: No module named numpy.
I read somewhere that numpy 1.6.2 is for Python 3.x, so I also tried the above steps with numpy 1.5.1, and I got the same ImportError.
I'm speculating that the solution lies in some environment variable gymnastics, but I'm not sure what files/directories Python needs to "see" that isn't in scope. Any suggestions for how to get numpy working?
I also tried some precompiled binaries for RHEL, but they gave various errors when I did sudo yum install [numpy precompiled binary url].rpm.
As an aside, my motivation for installing numpy is to use PyGnuplot. Also, I've installed numpy and PyGnuplot on other machines before, but it's been on Ubuntu and Mac OS.

RHEL6 ships numpy 1.4.1, see distrowatch. If 1.4.1 is new enough for you, you can install it with:
$ yum install numpy

When I install Python packages on Ubuntu using setup.py packages end up in
/usr/local/lib/python2.7/dist-packages/
assuming Python2.7
If numpy is installed there, you will need to append this path to your Python's path:
export PYTHONPATH=$PYTHONPATH:/usr/local/lib/python2.7/dist-packages/
you can append it permentanly using ~/.profile
Another way is by adding a .pth to a directory that’s already on Python’s path, for example
echo "/usr/local/lib/python2.7/dist-packages/" > /usr/local/lib/python2.7/site-packages/dist_pkg.pth
run that last command as root of course

I gave up on using RedHat, and I installed Ubuntu in a VM. It was a one-liner using apt-get.
Not an ideal solution to the question at hand, but I just didn't want to spend any more time chasing down a solution for RedHat.