Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "In Flask, a configuration is done on an attribute named config of the Flask object."

A block of code is set as follows:

from flask import Flask 
app = Flask(__name__) 
 
@app.route('/') 
def hello_world(): 
    return 'Hello to the World of Flask!' 
 
if __name__ == '__main__': 
    app.run() 

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

from flask_wtf.file import FileField, FileRequired 
 
class Product(db.Model): 
    image_path = db.Column(db.String(255)) 
 
    def __init__(self, name, price, category, image_path): 
        self.image_path = image_path 
 
class ProductForm(NameForm): 
 image = FileField('Product Image', validators=[FileRequired()]) 

Any command-line input or output is written as follows:

  $ pip3 install Flask

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "It can also handle the Remember me feature, account recovery features, and so on."