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Pip broken after deleting python3.7 folders

I think I broke my pip after desperately trying to uninstall Python3.7. (I am on a Mac)
I removed the python folder from the application, removed /Library/Frameworks/Python.framework and removed the folders from /usr/local/bin according to https://osxuninstaller.com/uninstall-guides/properly-uninstall-python-mac/. I then installed python3.6.
src$ pip3.6 --version pip 9.0.1 from
/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages
(python 3.6)
but pip itself does no longer work.
src$ which pip
/usr/local/bin/pip
src$ pip --version
-bash: /Library/Frameworks/Python.framework/Versions/3.7/bin/pip: No such file or directory $
It still references the python 3.7 folder. How can I unlink that reference? THe same is btw. true for the package virtualenv that I installed. I can install it with pip3.6 but calling virtualenv still references to the framework folder of 3.7

You need to install pip in that environment. i.e 3.7.
Reason is when you deleted the default install you deleted the dependencies/ libraries that came with it.
Easiest way is to install python afresh via homebrew if you have it.
brew install python
Alternatively you can follow the instructions here to download a file to install pip securely. Homebrew can become messy when managing python environments. I'd recommend looking at something like anaconda if you are going to using different python versions with their own dependencies etc.
curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
python get-pip.py
https://pip.pypa.io/en/stable/installing/#installing-with-get-pip-py
Other options for fresh install are described in answer here. Hope that helps.
How do I install pip on macOS or OS X?

How to completely reset everything Python to default in Ubuntu 18.04?

Edit:
So now which pip, which python and which python3 have started working correctly somehow. I was also able to install libraries using pip. The only remaining problem is that of the apt_pkg. Running apt-get install python-apt gives:
Reading package lists... Done
Building dependency tree
Reading state information... Done
python-apt is already the newest version (1.6.3ubuntu1).
Running any python application still gives error: ImportError: No module named apt_pkg
Running echo $PATH returns:
/home/hamza/bin:/home/hamza/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
Running find /usr -name python -o -name python3 returns:
/usr/local/lib/python3.5/dist-packages/notebook/static/components/codemirror/mode/python
/usr/local/lib/python2.7/dist-packages/notebook/static/components/codemirror/mode/python
/usr/lib/python3
/usr/lib/gimp/2.0/python
/usr/lib/libreoffice/share/Scripts/python
/usr/lib/virtualbox/sdk/bindings/xpcom/python
/usr/lib/wx/python
/usr/bin/python
/usr/bin/python3
/usr/share/code/resources/app/extensions/python
/usr/share/bash-completion/helpers/python
/usr/share/bash-completion/completions/python
/usr/share/bash-completion/completions/python3
/usr/share/python
/usr/share/javascript/codemirror/mode/python
/usr/share/python3
/usr/share/lintian/overrides/python
/usr/share/lintian/overrides/python3
/usr/share/gcc-8/python
/usr/share/gdb/python
/usr/share/librevenge/python
/usr/share/doc/python
/usr/share/doc/python3
/usr/share/doc/python-statsmodels/examples/python
/usr/share/playonlinux/python
Original:
Python on my system is a wreck. I have got multiple versions installed. None work properly. Apparently some applications using python are not working either (eg: Unity Tweaks). My python libraries will not install because pip doesn't work, although it says it is already installed
I was trying to install some libraries for python on my system using pip. Turned out pip was not working. I tried to reinstall pip only to learn that pip was already installed. I went through a process of understanding the difference between python and python3. I have tried enough things and have basically lost track of the things I have done to get the libraries installed. Long story short, pip does not work no matter what, my libraries will not install and consequently my code doesn't run.
Here is some of the things I have already done:
which pip
This return no output
apt-get install python-pip
Says I have pip already installed
apt-get install python-apt
To resolve ImportError: No module named apt_pkg. It says:
Reading package lists... Done
Building dependency tree
Reading state information... Done
python-apt is already the newest version (1.6.3ubuntu1).
But the error persists
And countless other stuff I do not remember.
What I want now is simple. I wish to somehow get out of this hassle by resetting all of my python settings and installation to default, and then install the pandas and numpy libraries for my system. Any and all help would be appreciated.
Result for python -m pip -V:
pip 9.0.1 from /usr/lib/python2.7/dist-packages (python 2.7)
Result for python3 -m pip -V:
pip 9.0.1 from /usr/lib/python3/dist-packages (python 3.5)

One of the following commands worked for me:
pip3 install -U pip
python -m pip install -U pip
python3 -m pip install -U pip
Make sure the version of your python3 is 3.6, which is the default version of ubuntu18, then upgrade pip.
export py3_path=`which python3`
rm $py3_path
ln -s `which python3.6` $py3_path
python3 -m pip install -U pip
Or use pyenv to manage multi versions https://github.com/pyenv/pyenv

Brew install python not pointing to python anymore

I am trying to install jupyter on mac,
I understand that the mac comes with python version installed
But i also installed brew and installed python through brew.
When i check python location i get:
which python
/usr/bin/python
When i check pip location i get:
which pip
/usr/local/bin/pip
When i try to install jupyter:
pip install install
after a long installation it tried to remove python package that it want's to upgrade
And fails:
On trying to uninstall dateutil.
I think its the mac packages.
I tried with sudo, no change.
As far as i can understand it because the files are immutable.
Tried to remove the immutable with:
chflags uchg.
No change.
I also tried to work with virtual env, using:
sudo pip install virtualenvwrapper.
But that pip tries to uninstall another python folder.
Any suggestions?
Thanks
UPDATE:
The brew seems to create links from python2. to python2
And the same for python3.
I tried to create the link myself, It worked and i was manage to install the package i wanted. But its not a good solution,
The all point of brew is to manage this things for me, next time i will upgrade python it will break.
Any suggestions why? could it be because the brew installed two python version on my laptop?
RESOLVED:
Found the answer, thanks to #tdube question i went and looked what brew guys did to python and found this thread from Jan 17.
I turns out that they changed the behavior or installing python.
No you don't have simply python any more.
You have python2 and python3.
No more simply pip, now you have pip2 and pip3.
That is a major change from the default behavior of how people use python
Especially that mac comes with a default python
so now you have
python that is /usr/bin/python
python2 that is /usr/local/bin/python2
python3 that is /usr/local/bin/python3
this is the fix, the brew guys suggest ( you can see it when running brew info python ):
==> Caveats
This formula installs a python2 executable to /usr/local/bin.
If you wish to have this formula's python executable in your PATH then add
the following to ~/.zshrc:
export PATH="/usr/local/opt/python/libexec/bin:$PATH"
Pip and setuptools have been installed. To update them
pip2 install --upgrade pip setuptools
You can install Python packages with
pip2 install <package>
They will install into the site-package directory
/usr/local/lib/python2.7/site-packages
See: http://docs.brew.sh/Homebrew-and-Python.html
You can read about it in this thread:

The Python that comes "pre-installed" on Mac is located in /usr/bin/python. I think you need to change the order of the entries in your PATH environment variable as noted here (python homebrew by default). Which file your PATH is set in depends on which shell you are using.

Where should python pip install?

I am using a raspberry pi 2 board with Raspian. In order to be consistent with my mac I created a separate version of Python v2.7.10. I installed a number of packages that where recommended and I was able to compile it. I placed it in /usr/local/opt/Python2.7.10. I then updated my path environment so that this directory comes first. The original Python 2.7.3 is located at /usr/bin
Now I need to get pip installed. I downloaded get-pip.py and executed it. pip was installed in /usr/local/bin, which is not where either versions of Python exists. This doesn't look right to me. I am not sure if this pip is for the original Python or for the newer version of Python that I created. I just don't want to mix the two. Is this the correct location or do I need to get it somewhere in /usr/local/opt/? I am not sure how to get pip to install in /usr/local/opt/Python2.7.10/bin.

pip: dealing with multiple Python versions?
To use pip on a specific Python, you need to make sure you have downloaded pip and installed pip for that python version:
curl -O https://bootstrap.pypa.io/get-pip.py
/path/to/python27 get-pip.py
Then use specific pip version to install packages:
pip2.7 install somePackage

installing packages over pythonbrew

I installed python 2.7 with python brew. How do I install packages to work with it? I installed MySQLdb with synaptic, but I am unable to import it in python 2.7.

Switch to 2.7:
pythonbrew switch 2.7
Curl and run get-pip to get the correct version of pip for 2.7:
curl -O https://raw.github.com/pypa/pip/master/contrib/get-pip.py
python get-pip.py
This will install the version of pip for 2.7. Check it by doing:
pip --version
Turn off pythonbrew:
pythonbrew off
Check the version of pip again, and it should be using the one for your default Python:
pip --version
If all is good, then switch back to 2.7 in pythonbrew and install mysql-python for 2.7:
pythonbrew switch 2.7
pip install mysql-python
Check to see that it is installed for 2.7:
pip freeze
Pip freeze will give you a listing of all installed libraries for the current active version of Python.

You should try to install pip, which is a recursive acronym: Pip Installs Packages. This thread talks about installing it on windows, on Ubuntu I did sudo apt get install pip.
Ok, your problem is that "mysqldb" is not a python package. You need to use MySQLdb as a backend, or simply install sqlite3 and import that into Python, which is a module that mimics SQL. If you end up using an actual full-on database, like MySQLdb or PostgreSQL, you'll probably need to install SQLAlchemy, which is a Python module to interface with those.

You need to install a version of pip for each Python version. Do you have easy install available? If so you can do
easy_install-2.7 pip
Is there a specific reason that you are installing Python via home brew though? You do know that Ubuntu has as a package.
sudo apt-get install python2.7
Will give you a version of Python that is already nicely set up.
I also believe that you should be trying to install the Python package called mysql-python.
pip install mysql-python
MySQLDB is not a Python package. It's the actual database.

Agree with #leta-rogers. However, I didn't have to install pip separately. Installing python using pythonbrew installed pip (for python 2.7) for me as well:
pythonbrew install 2.7
pythonbrew switch 2.7
pip install mysql-python