Installing virtualenvwrapper on macOS Sierra - "-bash: /usr/local/bin/virtualenvwrapper.sh: No such file or directory" error
You have a mix of pythons on your machine. I would stick to one.

In this case I would stick to anaconda.

SO edit your path so that anaconda is first on the path before /usr/local/bin and /usr/bin

Test by running 

 which python  


You should get

/Users/mark/anaconda3/bin/python


If a 2 rather than 3 you have python2,7 and I would switch to 3.

You can now use virtulenv etc as they are part of python 3.6 (the current 3.x version) see the python docs You should use venv now not what your tutorial shows https://docs.python.org/3/library/venv.html

However as you are using anaconda you can use conda insteaf of venv, You will find most things already installed (I use conda as it provides prebuilt C libraries when needed, pip etc can be more complex and also could require Xcode) https://conda.io/docs/user-guide/getting-started.html The django install is at https://anaconda.org/anaconda/django