Conventions used

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

Code in text: 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: "Mount the downloaded WebStorm-10*.dmg disk image file as another disk in your system."

A block of code is set as follows:

resource = {
    "api_key": "AIzaSyDYKmm85kebxddKrGns4z0",
    "id": "0B8TxHW2Ci6dbckVwTRtTl3RUU",
    "fields": "files(name, id, webContentLink)",
}

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

#casestudy1.py: Pi calculator
from operator import add
from random import random
from pyspark.sql import SparkSession
spark = SparkSession.builder.
master("spark://192.168.64.2:7077") \
    .appName("Pi claculator app") \
    .getOrCreate()
partitions = 2
n = 10000000 * partitions
def func(_):
    x = random() * 2 - 1
    y = random() * 2 - 1
    return 1 if x ** 2 + y ** 2 <= 1 else 0
count = spark.sparkContext.parallelize(range(1, n + 1),   partitions).map(func).reduce(add)
print("Pi is roughly %f" % (4.0 * count / n))

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

Pi is roughly 3.141479 

Bold: Indicates a new term, an important word, or words that you see onscreen. For instance, words in menus or dialog boxes appear in bold. Here is an example: "As mentioned earlier, Cloud Shell comes with an editor tool that can be started by using the Open editor button."

Tips or important notes

Appear like this.