pip and virtualenv goes missing

[Niyojan]

Microsoft Windows [Version 10.0.15063]
Python version (manually compiled, its NOT altinstall)

Python 2.7.13 (default, Jun 11 2017, 17:56:07)
[GCC 4.8.4] on linux2

pip(which is a python package manager) and virtualenv suddenly goes missing. They were working just sometime back and its not there anymore.

I am trying
virtualenv my_env
Output:
The program 'virtualenv' is currently not installed. You can install it by typing: sudo apt-get install python-virtualenv

So I try:
sudo apt-get install python-virtualenv
I get:

The following information may help to resolve the situation:

The following packages have unmet dependencies:
 python-virtualenv : Depends: python-pkg-resources but it is not going to be installed
                     Depends: python-setuptools but it is not going to be installed
                     Depends: python:any (>= 2.7.1-0ubuntu2)
                     Recommends: python-pip (>= 0.7.2) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

So I try apt-get update and upgrade and cache clean and -f and all other things, but still the same error, Finally I use
sudo aptitude install python-virtualenv
It gives:

      Keep the following packages at their current version:
1)      python-chardet [Not Installed]
2)      python-colorama [Not Installed]
3)      python-distlib [Not Installed]
4)      python-html5lib [Not Installed]
5)      python-pip [Not Installed]
6)      python-pkg-resources [Not Installed]
7)      python-requests [Not Installed]
8)      python-setuptools [Not Installed]
9)      python-six [Not Installed]
10)     python-urllib3 [Not Installed]
11)     python-virtualenv [Not Installed]
12)     python-wheel [Not Installed]

      Leave the following dependencies unresolved:
13)     python-pip recommends python-wheel
14)     python-virtualenv recommends python-pip (>= 0.7.2)


Accept this solution? [Y/n/q/?] Y
No packages will be installed, upgraded, or removed.
0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B of archives. After unpacking 0 B will be used.

So I thought virtualenv is now install, but its still not there.

I try also try to install pip, same result
sudo apt-get install python-pip

Then I thought of installing pip manually, using python get-pip.py, so I try to copy the content of https://bootstrap.pypa.io/get-pip.py in a file, like
vim get-pip.py
Activate insertion using 'i'
as soon as i paste, bash hangs indefinitely .

finally i had to do this

wget https://bootstrap.pypa.io/get-pip.py
sudo python get-pip.py
pip install virtualenv

That installed everything as expected, but it was lot of work :(

[anzellai]

Where did you compile your Python to? /usr/lib or /usr/local? Sometimes system wide installation can go into either locations...

Also have you tried installing virtualenv via pip install --user virtualenv? That should install the executable at $HOME/.local/bin, and this directory should be included in your PATH environment.

I found installing with --user flag has a more predictable behaviour as packages can be located in a centralised user space.
Not sure if that will be helpful for your case, as you go for compiling Python manually.

[Niyojan]

/usr/local/bin/python is now my default python.

I didn't tried using pip install --user virtualenv but, it wouldn't have worked as pip itself went missing.

[itiic]

On Ubuntu: VERSION="18.04.2 LTS (Bionic Beaver)"
sudo apt install virtualenv
works

[marcofuentes05]

Using wsl with Ubuntu 20.04, I´ve installed virtualenv both via pip and apt-get and it still does not work. The error message is:
"The virtual environment was not created successfully because ensurepip is not
available. On Debian/Ubuntu systems, you need to install the python3-venv
package using the following command.

apt-get install python3-venv

"

[nofreewill42]

apt-get install python3.9-venv
for me