Where do i enter pip install flask-mysql?
You should be able to type it in the command line for your operating system (ie. CMD/bash/terminal) as long as you have pip installed and the executable location is in your PATH.
Am implementing a sign up using python & mysql. 
Am getting the error no module named flask.ext.mysql and research implies that i should install flask first. They say it's very simple, you simply type
pip install flask-mysql
but where do i type this? In mysql command line for my database or in the python app?