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• This book will teach you on how to build fully featured web applications with database integration.
• Also with making REST service.

• The name of application variable is usually app.
• The argument __name__ is used to tell the application where to look for resource (for example, static contents or templates).

• Flask can handle basic routing as well.

• There is this urlparse library to verify whether a string is a valid URL path or not.
• Above image is a simple example of the implementation of the urlparse.

• This book uses Python 2.x.

• Python 2.x is usually default in Linux distribution.

• Some packages that need to be installed, sudo apt-get install python-dev python-pip.
• The author of this books uses Linux Mint, hence the packages comes from Linux Mint repository.
• pip is the package manager for Python. Similar to NPM of NodeJS.

• Install virtual environment so that the dependencies of the project is exclusive to the virtual environment and are not system wide.

sudo pip install virtualenvwrapper
echo "source /usr/local/bin/virtualenvwrapper.sh" >> ~/.bashrc

• Example command on how to make Python virtual environment and then install Flask.

mkvirtualenv hello
pip install flask

• However this is my preferred ways to install and use Python virtual environment.
  • Install Python virtual environment using pip with sudo pip install virtualenv.
  • Or, in Ubuntu you can install it from the Ubuntu repository, sudo apt-get install python-virtualenv.
• The to make the Python virtual environment.

mkdir project_name
cd project_name
virtualenv venv
. venv/bin/activate
pip install flask

• . venv/bin/activate is used to go inside the virtual environment.
• To go out from the virtual environment use this command deactivate.

• This book method on how to use Python virtual environment.

• Use # coding:utf-8 in the beginning of the Python entry file (usually main.py) to tell Python to use utf-8 encoding.
• This helps you to prevent nasty bugs exists within the application.