Verify you are installing flask for your correct python version inside your virtual environment.

I’ve came across the problem:

bash: flask: command not found

And the first StackOverflow answer was:

Flask 0.10 has no flask command, it was added in 0.11.

But my version of flask was 1.0.2, so why I do not have the flask command?

It happened that I was installing it for a different python version inside my virtual environment (venv).

Verify your python environment for flask installations:

mortiz@florida:~/Documents/projects$ pip freeze |grep -i flask
mortiz@florida:~/Documents/projects$ pip2 freeze |grep -i flask
mortiz@florida:~/Documents/projects$ pip3 freeze |grep -i flask

First find out your python version «inside your (venv)»

mortiz@florida:~/Documents/projects/python/APIS/new_project_py_2_7$ which python

(venv) mortiz@florida:~/Documents/projects/python/APIS/new_project_py_2_7$ python --version
Python 3.5.3

Installation of flask for python3

pip3 install flask
python3 -m pip install flask

Installation of flask for python2

pip2 install flask
python2 -m pip install flask

Installation of flask for default python (be careful if you are inside your (venv) or in your shell)

pip install flask
python -m install flask