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: "Python has other statements, such as global or nonlocal, which modify the rules for variables in a particular namespace."

A block of code is set as follows:

s = 0 
for n in range(1, 10): 
    if n % 3 == 0 or n % 5 == 0: 
        s += n 
print(s) 

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

s = 0 
for n in range(1, 10): 
    if n % 3 == 0 or n % 5 == 0: 
        s += n 
print(s) 

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

$ pip install pillow beautifulsoup4 PyMonad

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: "For our purposes, we will distinguish between only two of the many paradigms: functional programming and imperative programming."