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pip install, installing packages for other python version

I am working on a GPU instance on AWS. There are some already provided Conda environments. I am using tensorflow2_latest_p37 environment.
This environment has 2 python 3 versions .i.e python 3.6 and python 3.7.
All the preinstalled packages are available in python 3.7
But whenever I am trying to do pip install dlib it would install it for python 3.6.
How can I install this for python 3.7?

Run the command:
which python.
Probably it will show you python3.6,
it means that your default python version is 3.6.
You need to search your pip3 path.
path/to/pip3 install dlib.

If you know how to use the Python 3.7 environment, you can simply use python -m pip install ... or more exactly:
command_for_python3.7 -m pip install package_name
If unsure, you should search for commands starting with python in /bin, /usr/bin and /usr/local/bin. You could also have Python installations under /opt.
On Windows, the magic word is py:
py 3.7 -m pip install package_name

How to change default install location for python?

I am using RedHat Linux.
Python 2.6 is already installed in usr/src/bin. When I install Python 2.7, it gets installed in usr/local/src/bin.
Further, I need to install sklearn. When I try installing sklearn using pip, it refers to Python2.6 and not Python2.7.

You can run python -m pip to see if pip is using the right version of python
I think you can probably specify the location with usr/local/src/bin pip install If you're sure that's where python 2.7 is installed. If pip is not using python 2.7 you should reinstall pip in the correct version.
There is another question which could help solve yours:
Pip Install not installing into correct directory?

How to install pip with a specific python version

I want to install pip for python 2.7, but I am also having python 3.x but both locations are different. when ever I install or update the pip It is installing in the python 3.x location.
How to install pip for python 2.7?

I recently found the following solution, when you are maintaining python2.x and python 3.x in host system. You can find the pip under Scripts folder.
Try pip --version it gives pip version and python version as well
If you want to install package using pip use the following commands.
python -m pip install package_name
python2.x -m pip install package_name
Which reads the specified python pip module to install the package

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

Installing pip with correct python version

I am on shared hosting and I need to install pip with the correct python version, 2.7. To install pip, I did:
$ easy_install pip
However, after it was installed I get the following:
[dave#web1 lib]$ pip --version
pip 1.0.2 from /home/premiere/dave/financials/lib/pip-1.0.2-py2.7.egg (python 2.4)
How would I re-install pip to work on the python2.7 version, which is also installed on the machine?
[premiered#web1 ~]$ python --version
Python 2.6.6
Which is strange, since it is installing to python2.4.

You may want to create a virtualenv using -p /path/to/python-2.7.binary param, and then activate it. Then all stuff you installed using pip would be correctly into your virtualenv.

If multiple versions of python are installed on the system, then you should invoke the version you want when installing. i.e.
$ python27 easy_install pip
This creates a pip file in your path that contains the specified version of python in the hashBang line.