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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: "To specify the position within the grid, the row, and column keywords are used."

A block of code is set as follows:

self.label_text = tk.StringVar()
self.label_text.set("Choose One")

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

def say_hello(self):
    message = "Hello there " + self.name_entry.get()
    msgbox.showinfo("Hello", message)

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

>>> import tkinter
>>> tkinter.TkVersion

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: "The last thing to do is to create the method that will be responsible for placing it into our Tools menu."

Warnings or important notes appear like this.

Tips and tricks appear like this.